Third-party social web browser developer RockMelt announced today that it has established a long-term partnership with Facebook’s engineering and design teams to build the newly released RockMelt Beta 3 and future products. Along with an improved Chat and integrated Notifications, Requests, and Messages experience, Facebook.com appears differently when browsed through the new version of RockMelt, with elements including Chat and alerts hidden from view since they appear in the browser.

The partnership with the 40-employee RockMelt will allow Facebook to guide the development of a web browser without expending nearly as many resources as would have taken to release one itself. It could also lend legitimacy to RockMelt, which says it has only had 1 million people try its product to date, though its few hundred thousand active users log an average of 6.5 hours a day on the product.

Six months ago RockMelt launched the private beta of its social web browser, designed to pull frequently used parts of Facebook, Twitter, and blogs inside the browser chrome. Beta2 saw the addition of multi-friend Chat support, further updates allow it to pull in data from YouTube and RSS, and the public beta launched 10 weeks ago.

User adoption of the Andressen-Horowitz-backed project or other social browsers such as Wowd has yet to explode. Still, founders Eric Vishria and Tim Howes are optimistic. “Over 500 million people have switched browsers in the last three years,” they told us. “81% of our users are 34 or younger. For those in the social generation, it just makes sense. Conversion rates and retention are high. They just get it.”

A deeper integration with Facebook offering unique value could kickstart growth.”There’s no way this release would happen without them,” Vishria and Howes told us. “We’re interacting with them five times a day to get this done.” Though Facebook is hiring for a Seattle-based desktop software team, RockMelt said it was working with a Palo Alto team from Facebook headquarters. This may support our prediction that Facebook’s desktop team isn’t building a browser, but instead software such as media usage scrobbling widgets that will help users share their music listening and video watching habits.

RockMelt Beta3′s New Features

Downloadable starting at 10am PST today, RockMelt Beta3 features several new features that allow browser chrome customization and streamline social experiences. Users can now swap the dock-like App Edge and the buddy list-esque Friend Edge between the left and right rails of the browser. The Friend Edge can be clicked to expand and show the names of friends instead of just their profile pictures, which can be hard to identify.

When a friend in the Friend Edge is clicked, it starts a Facebook Chat with them that automatically imports your Chat history. RockMelt Beta3 works with Facebook’s unified messaging product to seamlessly switch from Messages to Chat if a friend is online. A user’s Notifications, Requests, and Messages all appear in the top center of the chrome with counters denoting new activity.

Perhaps most interesting though is what Facebook’s team has done to change Facebook.com when visited through RockMelt. Rather than appear redundant, a user’s Chat buddy list and alerts don’t appear on the site, only in the browser. Clicking within Facebook to initiate a Chat opens the Chat in RockMelt instead, so users can carry on the conversation even as they browse other sites.

Outsourcing the Facebook Browser

Vishria and Howes tell us RockMelt Beta3 is “the beginning of what the modern browser looks like”. They say there’s many more social features to build out as part of the Facebook partnership, including “creating an unbelievable photo experience, Places, Like integrations — we’re constantly brainstorming and collaborating.” The companies may have been connected by Marc Andressen, both a Facebook board member and a core RockMelt investor who believes RockMelt could be the fifth browser to reach over 100 million users.

RockMelt’s 40-person engineering and design-focused team builds on Google’s Chromium open source browser which has 200 devs, which is turn built on WebKit that has its own army of open source devs. Without an overwhelming user demand for social browsers, developing one internally could be a strategic misstep for Facebook, but working with RockMelt might accomplish similar goals much more efficiently. This way, Facebook can work on more crucial or unexpected projects while still keeping its small size and startup culture.

Comedian Martin Lawrence topped our list of growing Facebook Pages by the number of Likes, probably due to a Page consolidation. Then there was a group of big brands, a range of movie and TV shows, but most of the list was made up by musicians’ Pages. The Pages on our list grew from between 562,300 and 1 million Likes, we measure the growth of Pages with our PageData tool.

Top Gainers This Week

	Name	Likes	Gain	Gain,%
1.	Martin Lawrence	3,992,451	+1,084,230	+37%
2.	Katy Perry	28,882,983	+1,054,324	+4%
3.	Facebook	45,750,505	+1,036,208	+2%
4.	YouTube	39,151,934	+995,846	+3%
5.	Shakira	34,252,803	+863,806	+3%
6.	Rihanna	37,891,862	+863,606	+2%
7.	El Club de la Comedia	852,279	+852,279	+0.0%
8.	Eminem	40,789,843	+842,400	+2%
9.	The Simpsons	30,013,366	+729,391	+2%
10.	Lady Gaga	38,336,808	+697,470	+2%
11.	AKON	25,717,879	+681,783	+3%
12.	Coca-Cola	30,675,401	+667,006	+2%
13.	Family Guy	33,285,307	+617,104	+2%
14.	Black Eyed Peas	20,816,578	+598,130	+3%
15.	Linkin Park	30,562,645	+589,013	+2%
16.	Avril Lavigne	22,113,699	+582,765	+3%
17.	South Park	29,992,401	+579,774	+2%
18.	Harry Potter	26,505,637	+574,827	+2%
19.	Usher	21,076,163	+567,564	+3%
20.	Beyoncé	24,060,001	+562,250	+2%

As mentioned, Martin Lawrence’s Page grew more than 1 million Likes to 3.9 million over the course of one day; this is most likely to do a Page consolidation. Big brands on the list included Facebook, growing over 1 million Likes to 45.7 million, and  YouTube, growing 995,800 Likes to 39.1 million.  Coca-Cola also made the list, adding 667,000 Likes to push past 30.6 million.

An interesting list of TV and movie Pages made our list, too.

“El Club de la Comedia” is a Spanish language comedy show that said on the Page it’s “back” on TV, consequently adding all of its 852,300 Likes this week. “The Simpsons” grew by 729,400 Likes to surpass a total of 30 million; the Page featured a show-related quiz this week. “Family Guy” grew to 33.2 million by adding 617,100 Likes this week after promoting the show and related merchandise. “South Park” added 579,800 likes to come in just under 30 million; the Page promoted related Comedy Central and creators’ projects this week. Finally, “Harry Potter” saw 574,800 more Likes, taking the Page to 26.5 million after releasing more movie posters for the upcoming July premiere of the next film.

Then came the music Pages.

Katy Perry added more than 1 million Likes after promoting her tour and latest video. Shakira’s Page grew by 863,800 Likes to 34.2 million by promoting her latest video and single. Eminem also used videos to grow his Page from 842,400 Likes to 40.7 million. Rihanna hasn’t been using videos, but photos with fans at her concerts, to grow her Page 863,600 Likes to 37.9 million.

Lady Gaga saw 697,500 Likes more to reach 38.3 million on Facebook after promoting her media appearances. AKON saw 681,800 Likes more to his 25.7 million by promoting his upcoming video. Black Eyed Peas were scheduled to perform for free in New York City, but it was rained out; nonetheless the band added 598,100 likes to surpass 20.8 million Likes on the Page. Linkin Park grew by 589,000 Likes to 30.5 million by promoting their music and media appearances. Avril Lavigne’s Page grew by 582,800 Likes to reach 22.1 million with personal video and photo updates. Usher saw 567,600 Likes to pass 21 million with video updates and media/tour updates. Finally, Beyoncé’s 562,300 new Likes put her over 24 million as she promotes her upcoming album.

Last Friday, Facebook relaunched the Comment View for photo albums, which displays photos at roughly half of full-screen and sorts them by those most recently commented on. Users can switch from Grid View to Comment view with a switch in the top right of albums.

The feature will be especially helpful to Page moderators who otherwise had to sort through notifications about feedback or look at photos one by one to moderate comments on their photo albums.

The team responsible for reviving Comment View, news feed engineer Dan Schafer, Photos engineer Nathanial Roman, and commerce team designer Brynn Shepherd told us the feature was developed as a Facebook Hackathon project. Facebook used to provide the Comment View for albums, but removed it last year as part of a simplification of the Photos product.

The team, who were originally Facebook interns together, heard complaints from users and friends about the removal of the Comment View, and also wanted to use it themselves. So they built the new iteration from scratch at one of Facebook’s internal Hackathons where employees are encouraged to work on projects they think could benefit the company, even if they’re outside their specialty. Their interest and complementary skill sets made the Comment View an “ideal Hackathon project.”

Now admins can use the feature to quickly see what people are saying about the photos hosted on their Pages. Since photos with no comments don’t appear in the Comment View, and they’re sorted by most recent activity, photo feedback moderation through the feature is much more efficient than through notifications or the standard view.

Users who come across the Comment View can also make use of it to quickly hop between conversations with friends on a big album of vacation photos they’ve just uploaded. However, there won’t be any flash prompts encouraging users to try it out, just a small title when the toggle switch is hovered over. The team told us “We didn’t want to go to crazy with introducing it since it used to exist. It’s the type of feature that if they really like, they’ll find it again.”

Strategies for replying to fans and using Facebook’s native Page moderation tools can be found in the Facebook Marketing Bible, Inside Network’s comprehensive guide to marketing on Facebook.

Companies hired more interns in the past seven days as well as a few sales staffers. Most notably, Buddy Media said that it had hired veteran financial executive Dennis Morgan last week as its new chief financial officer. He has previously served as the CFO of three venture-backed companies, including EPAC Technologies, Panther Express and Vibrant Media, and served for a time as the Vice President of Corporate Finance at Yahoo.

If your company is hiring new people or making a notable promotion, please let us know. Email mail (at) insidefacebook (dot) com, and we’ll get it into next week’s post. Also, please note that information about most new hires, below, comes directly from company updates from LinkedIn.

Looking for new opportunities? Check out the Inside Network Job Board, which shows the latest openings at leading companies in the industry.

Here’s this week’s list of hires:

Buddy Media

• Kendell Burton, Design Intern
• Dennis Morgan, CFO

Context Optional (part of Efficient Frontier)

• Dawn Thawnghmung, Recruiter – formerly a Continuous Improvement Analyst at Meyer Tool.

Involver

• Jamie Lipson, Marketing Intern

Wildfire

• Noah Abelson, Sales Associate - formerly the founder and co-director at Flavor of Change LLC.
• Adam Khalifa, Business Development – previously a consultant at Freelance New Business Development Libya.

Work4 Labs

• Sadhika Batra, Marketing & Sales Strategy Intern

In the Developer Blog’s latest Platform Update, Facebook announced that developers can now view the page load times for their applications in Insights. It also listed iframe dialog permissions that are no longer permitted, and noted that Open Graph page images must have a minimum width of 180 pixels to be displayed next to posts made by that page.

Now, if developers include the call FB.Canvas.setDoneLoading from the Javascript SDK in their Canvas iframe applications, their app Insights Dashboard’s Performance tab will show their page load times in milliseconds. Facebook’s documentation states that the load time is tracked “beginning from the time when the first bytes arrive on the client, and ending from the point at which you call this function.”

Developers can also use the stopTimer and startTimer calls to exclude portions of the loading time from being counted. The addition of this data to Insights will make it easy for developers to identify loading issues and address them before they impact more of their user base. Developers can also track the connection between load time, conversion rate, and bounce rate to determine whether slow loading pages are hurting business.

For security reasons, Facebook has disallowed the use of iframe dialogs for requesting certain kinds of sensitive permissions after the initial authorization and permissions prompt. Those using the Javscript SDK won’t have to do anything, but those using display=iframemust now pop their own window and use display=popup to display the dialog. The following permissions are no longer allowed:

read_stream
manage_friendlists
read_mailbox
sms
xmpp_login
ads_management
read_insights
read_requests
manage_pages

The change will protect users from passing sensitive data or the ability to access their ad account, phone, inbox, Pages, Insights, and other important private content through a less secure channel.

Websites using the Open Graph markup language to help Facebook better present their content must now only use the og:image tag on images with a minimum width of 180 pixels if they want them displayed next to news feed updates they publish.

This means sites using the Like button should ensure their og:image tags are appended to large enough images if they take advantage of the ability to publish news feed updates to those that Like them.

Campaigns we featured this week used a few interesting and new ways of reaching out to Facebook users to grow their Pages, strengthen brand loyalty or align themselves with charitable causes. T.G.I. Friday’s let users buy each other beers with e-gift cards, State Farm Latino let users help Latin America by playing a game, Olympic Paint asked users to make their walls talk and Bergdorf Goodman takes fan engagement to a new level by asking its Facebook fans to become models for its latest campaign.

We’ve excerpted two of the campaigns below. You can see the full week’s coverage in the Facebook Marketing Bible, which also includes detailed breakdowns of dozens of other featured campaigns by top-performing brands and businesses on Facebook.

T.G.I. Friday’s Buy a Beer

Goal: Page Growth, Product Purchase, Engagement, Network Exposure, Brand Loyalty

Core Mechanic: A Facebook tab and app that allows users to send their Facebook friends a virtual gift card for a beer at T.G.I. Friday’s.

Method: The Buy A Beer tab on the T.G.I. Friday’s Page allows users to send an electronic gift card to their friends redeemable for an actual beer at the restaurant chain. The campaign is part of the chain’s in-store “Summer of Beer” push; users can send up to five beers to their friends at $5 per beer, or send a non-alcoholic beverage or food item.

Impact: The T.G.I. Friday’s Page has over 583,000 Likes and affords users several opportunities to share this offer with their friends via Facebook or Twitter. The launch of the app on June 9th caused the rate of new Likes to the Page to increase by roughly 25% in the few days afterwards.

State Farm Latino & Soccket’s Juega Hoy. Ilumina el Mañana.

Goal: Engagement, Product Purchase, Brand Loyalty, Network Exposure, Charity

Core Mechanic: A Juega e Ilumina tab with a wide variety of ways that users can interact with State Farm/Soccket’s campaign. The campaign aims to help provide Latin American countries with access to electricity.

Method: Users who visit the Juega Hoy. Ilumina el Mañana tab have ample opportunities to interact with videos, games, and spread the word about them. By interacting with these modules, users earn donations of Soccket balls (which generate electricity) to the region, while gaining the chance to download an exclusive iPhone app. On the tab there’s the option to use in English or Spanish, watch videos, Like and Share interesting content, support your favorite Latin American country and play a fun soccer game.

Impact: The State Farm Latino Page hosting the content has grown to 41,400 Likes, which could have been further boosted by this campaign had it been Like-gated. Overall the campaign’s hook of drawing users to participate and spend time on the site by offering a charity donation in exchange seems to be successful. What’s more, the actual integration is of a very high quality and this is reflected in the user’s experience playing the games or watching the videos. Companies can use similar alliances with charities to inspire more engagement with their campaigns, even if the actual value of the donations is very small.

How are top brands in the industry designing their Facebook marketing campaigns? See the Facebook Marketing Bible for detailed breakdowns of dozens of Featured Campaigns by top-performing brands and businesses on Facebook.

Did Facebook have fewer monthly active users in the United States at the start of June than it did at the start of May? What about user counts in other early-adopter countries like Canada and the United Kingdom? Is the company continuing to gain as many new users around the world now as it has in recent years?

As we covered yesterday, Facebook appears to have had fewer monthly active users at the start of June than at the start of May in the US and a few other countries — at least according to one data source — even as it has grown bigger than ever worldwide. Although today a person close to the company tells us that the site is “still growing in the US.”

Our data source was Inside Facebook Gold, our tracking service that shows country-by-country monthly active user counts, based exactly on the data that Facebook provides in its advertising tool. It showed Facebook falling from 155.2 million at the beginning of May to 149.4 million at the beginning of June, but growing by 11.8 million monthly actives around the world to reach 687.1 million over the same period.

Because this data can be buggy, delayed, or otherwise unclear, we regularly compare it against what leading third party measurement services show. Here’s the latest data available from Compete, comScore, Google Ad Planner and Quantcast.

A word of warning, though: Each of these other services has its own methodologies, and its own delays and bugs, so it’s important to look for trends that emerge from multiple sources over the months, not just what a given source says on a given month. Facebook, for example, self-reports its data in monthly active users, which isn’t exactly the same measure as the “monthly unique visitor” metric that third parties provide.

As you can see from our past posts, as well as from the data below, each data source does not exactly match with the others (here are the three most recent editions, if you’re interested). Let’s get started.

Compete

May stats are not yet available, but looking back to April, the firm shows Facebook falling from 140.7 million monthly unique visitors in March to 137.9 million in the US. In contrast to multiple other sources, Compete has shown Facebook gaining and losing users month-to-month over much of the past year.

It also shows Facebook’s most direct social product rivals, Twitter and MySpace, also losing users in April.

ComScore

While often more in line with the data in Facebook’s ad tool, comScore’s data tends to diverge a bit in the US and a lot internationally — or at least that’s what we’ve observed in the past (take a look at the top graph in this story for another divergent month: January of 2011).

In May, Facebook grew by 3.16 million monthly unique visitors, according to the firm, to reach 157.2 million in the country. It’s not clear why comScore is showing growth while Facebook itself is showing a loss. Twitter, meanwhile, made back some losses from April, while Myspace lost some of its gains from that month.

ComScore doesn’t have May worldwide numbers available yet, so here’s a look at March and April. Facebook had a slow month, growing by around 5 million worldwide, while MySpace made some unexpected gains, and Twitter fell again after many months of growth.

Google Ad Planner

In striking contrast to all other available stats, Google’s DoubleClick Ad Planner tool shows Facebook with 890 million unique visitors. It’s not clear why. The graph you see below shows Google’s count of Facebook’s daily unique visitors, based on browser cookies. This usage measure appears to have declined slightly from a high at the start of April back to 300 million.

Quantcast

More similar to Compete than the others, the firm shows Facebook with 139 million uniques by the end of April, growing slowly from previous months. Twitter and MySpace, meanwhile, also have a relatively flat trajectory.

Conclusion

As we say in every post we write about Facebook monthly user counts, a wide variety of issues cloud what is happening month to month. On the technical side, these can be philosophical differences in how each company measures usage — some are more reliant on buying data from internet service providers, or on gathering responses from user-installed toolbar trackers, to name two examples. Bugs can pop up for any of these services, including Facebook’s tool.

But as we noted yesterday, there do appear to be some overriding trends here. Canada, the United Kingdom and a few other early adopting countries have alternately shown gains and losses starting in 2010. Up until then, growth had generally been much steadier.

There’s an especially odd mix of data about the US. Most third parties showed Facebook with fewer monthly active users in January and February, but Facebook’s own data didn’t reflect that. Meanwhile, for May, the only third party to report numbers so far is showing growth, in contrast to the loss that Facebook is showing.

For its part, Facebook has not typically commented on traffic numbers, except when it publishes official statistics — the last time was when it hit 500 million monthly active users, months ago. After we published our first post yesterday, Facebook is clarifying to media outlets that data from ad tool isn’t intended for measuring traffic. To be sure. We use it anyway because it seems to be the most specific, and directionally accurate, despite the questions.

From time to time, we see stories about Facebook losing users in some regions. Some of these reports use data extracted from our advertising tool, which provides broad estimates on the reach of Facebook ads and isn’t designed to be a source for tracking the overall growth of Facebook. We are very pleased with our growth and with the way people are engaged with Facebook. More than 50 per cent of our active users log on to Facebook in any given day.

Facebook is trying to promote local business as well as complete the data of their listings with two new features on Places Pages: Recommend This Place and Community Edits.

The Recommend This Place sidebar module on the Pages of local businesses lets users write a short recommendations which are published to the news feed and shown on the Page to friends. Meanwhile, Cities now display a native tab called Community Edits that asks users to fill information such as address and category of popular Places in that city. These new features open an important new viral channel for local businesses and franchises, and allow Facebook to crowdsource improvements to its Places database.

For background, Facebook introduced Places and check-ins in August 2010, originally sourcing its local business database from Localeze. Changes to Localeze profiles are not necessarily synced with Places, though, leaving listings of new and evolving business out of date. After some scrapped attempts at allowing merges of Places and Pages for the same location, Facebook appears to have settled on adding Places functionality in the form of check-ins and maps to Pages listing a street address.

Recommend This Place

The site recently changed the Suggest to Friends feature for Pages so that only a Page’s admins could use it, and so the recommendations would appear in a sidebar module instead of the more prominent Requests channel. While fighting Page spam, it may have reduced the virality of Pages. But now with the launch of Recommend This Place, Pages with Places functionality have been given powerful new viral channel.

Appearing in the top right corner of Pages with a street address to users who live nearby, the module reads “Help your friends discover great places to visit by recommending [Page Name]” above a text field. Users can write a short recommendation, set its new feed visibility privacy setting, and submit it. The recommendation is then published to the news feed and displayed to friends browsing that Page in a “Recommendations From Friends” module in the right sidebar.

Recommend This Place will draw users to the Pages their friends prefer, and give users a social recommendation to Like the Page once they’re there. If Pages push their fans to complete the recommendations via Page updates and their info section, they could get viral exposure and grow their Like count for free.

Community Edits

In March Facebook began showing a small link on Places allowing users to “Suggest Edits”, or fill out missing data fields and submit them for approval. Now Facebook is looking to ensure that the most frequently checked in to locations provide useful information and are properly categorized. To do this, it has added a Community Edits tab the the left navigation menu of Pages for cities.

When clicked, the tab displays incomplete listing for five Places that receive a lot of check-ins in that city, and a header explains that “The Community Edits tab lets you share your knowledge about places in [city] and makes Facebook Places more useful. Add details about places, report duplicates, and more”. Users can then complete empty data fields such as ‘website’ and choose the proper category from a typeahead.

If users need help finding the data, a “Find on Bing” link beneath each entry brings up a Bing Maps search for the location, which sometimes includes the missing zip code or street address. It appears that Facebook’s maps deal with Bing does not cover automatically importing this data, so the social network is using this tab to task users with the chore. Unceremoniously, users are simply presented a new set of Places listings to complete when they finish a first, with no ‘thank you’ or ‘edits received’ message to inspire further assistance.

Users who explore the Community Edits tab and feel a deep loyalty to their city or to Facebook may be willing to perform data entry on their behalf. However, the feature doesn’t offer a clear reward such as authorship for a user’s contribution, nor does it properly applaud them. Facebook could improve the design and messaging of the feature to increase the potential volume of user generated edits the tab could drive.

Free Virality For Now

Recommend This Place and Community Edits may be a sign that Facebook knows helping small businesses get their Pages off the ground is in its own interest. As it did with games developers, offering early free viral exposure for Places could make return on investment cheap enough to lure businesses to market on the social network. Then by weening them off free virality, it could earn money switching them onto Facebook Ads to grow their fan base.

Strategies for using Facebook Places to market your business can be found in the Facebook Marketing Blible.

Most of the list of the top 20 growing Facebook applications by monthly active users this week allowed users to somehow interact with their networks of friends. There were also a few music-related apps, a few Page administrator apps and a handful of other types of titles.

Overall, the apps on our list grew from between 433,000 and 9 million MAU, based on AppData, our data tracking service covering traffic growth for apps on Facebook.

Top Gainers This Week

	Name	MAU	Gain	Gain,%
1.	Empires & Allies	9,655,503	+9,067,394	+1,542%
2.	Friend Buzz	8,222,173	+2,651,297	+48%
3.	60 Photos	14,409,927	+2,294,313	+19%
4.	BandPage by RootMusic	29,774,385	+1,249,092	+4%
5.	Monster Galaxy	14,689,968	+1,212,987	+9%
6.	Who loves you the most ?	1,647,282	+1,190,698	+261%
7.	Army Attack	2,587,595	+890,661	+52%
8.	Static HTML: iframe tabs	27,760,783	+770,742	+3%
9.	Your Luck [daily]	899,364	+762,360	+556%
10.	HTML + iframe + FBML = iwipa	8,818,781	+722,456	+9%
11.	Friend Matrix	2,068,624	+687,099	+50%
12.	Pieces of Flair	2,323,503	+632,139	+37%
13.	e-Diagnostics	3,280,122	+564,261	+21%
14.	Your World Rank	1,963,678	+518,126	+36%
15.	CityVille	90,348,826	+518,011	+0.58%
16.	Tu Amoor	1,648,557	+490,715	+42%
17.	Zoosk	10,142,002	+489,970	+5%
18.	Daily Horoscope	11,139,955	+480,222	+5%
19.	VEVO for Artists	6,547,761	+467,258	+8%
20.	PyramidVille	2,244,292	+432,928	+24%

We cover the social gaming apps rankings over on Inside Social Games. Those excluded, first was BandPage by RootMusic with 1.2 million MAU, followed by VEVO for Artists with 467,300 MAU. When it came to Page admin apps, Static HTML: iframe tabs grew by 770,700 MAU while HTML + iframe + FBML = iwipa grew by 772,500 MAU.

60 Photos grew by 2.3 million MAU; the app asks users to rate their friends’ Facebook photos, generating feed stories with positive ratings. Your Luck [daily] grew by 762,400 MAU; the app publishes a daily luck percentage to a user’s Wall every day. Pieces of Flair, which says it allows users to select from among different virtual gifts, grew by 632,100 MAU. Zoosk grew by about 490,000 MAU. Daily Horoscope grew by 480,200 MAU mostly in Turkey; the app publishes a daily horoscope to a user’s Wall.

The remaining titles were the aforementioned friend apps.

Friend Buzz grew by 2.6 million MAU. This app asks questions about a user’s Facebook friends and posts the answer to their Walls. Who loves you the most? is an app that grew by 1.1 million MAU. Friend Matrix grew by more than 2 million MAU the app is a Connect integration that creates a collage of your Facebook friends and then you can publish to your stream.

Then there was  e-Diagnostics with 3.2 million MAU, growing mostly in Indonesia. The app seems like an IQ test until the end when it asks you a bunch of questions about your friends, publishing feed stories like crazy. Your World Rank grew by 518,100 MAU mostly in India; the app publishes a set of stats, mostly about photos, to your Wall. Finally there was Tu Amoor with 490,700 MAU; the app asks romantic questions about your Facebook friends, publishing the answers to their Walls.

All data in this post comes from our traffic tracking service, AppData. Stay tuned for our look at the top weekly gainers by daily active users on Wednesday, and the top emerging apps on Friday.

Update, 6/14/11: Be sure to read our follow-up post on recent Facebook traffic according to third party measurement firms.

As we note below, we’ll need to wait to see what the long-term trends really are before knowing if Facebook is continuing to grow in the US and other countries.

Update, 6/15/11: More data is out from third party firms about May traffic. Our analysis here.

Facebook is still growing towards 700 million users, having reached 687 million monthly actives by the start of June, according to our Inside Facebook Gold data service.

Most of the new users continue to come from countries that are relatively late in adopting Facebook, as has been the trend for the past year.

But overall growth has been lower than normal for the second month straight, which is unusual.

The company gained 11.8 million more people over May, following 13.9 million over April. In contrast, it grew by at least 20 million new users over the typical month in the past 12; while there have been a few months that have registered lower growth numbers, they have not been back to back.

Why the drop? Most prominently, the United States lost nearly 6 million users, falling from 155.2 million at the start of May to 149.4 million at the end of it. This is the first time the country has lost users in the past year. Canada also fell significantly, by 1.52 million down to 16.6 million, although it has been fluctuating around that number for the past year. Meanwhile, the United Kingdom, Norway and Russia all posted losses of more than 100,000. If these countries — most of whom had adopted Facebook many years ago — had not lost users, and instead posted even small gains, Facebook would have had a much more typical month.

Going forward, we’ll be watching closely to see what longer-term trends emerge. Bugs in the Facebook advertising tool that we draw this information from, seasonal changes like college graduations, and other short-term factors, can influence numbers month to month and obscure what’s really happening.

Still, by the time Facebook reaches around 50% of the total population in a given country (plus or minus, depending on internet access rates in that country), growth generally slows to a halt, as we’ve noted before. So far, Facebook has been able to make up stalls and losses with big gains in heavily-populated developing countries like Mexico, Brazil, India and Indonesia. As you can see in the table above of the ten countries that gained the most users over May, this continues to be the case.

But how much further can it go if it is to reach its goal of 1 billion monthly active users? At least without getting into China — a move that as we and many others have noted, could both give it access to hundreds of millions of users and compromise its reputation in the US and many other countries around the world.