One might have guessed that the top app on this week’s AppData list of emerging Facebook apps would be one commemorating Thanksgiving. It’s true that an occasions-related app is at the top, but the American holiday seems to have passed the app world by; the top app is Birthday Greeting Cards, by Socialsoft.

Here’s the full list of the 20 fastest-growing apps still under a million monthly active users:

	Name	MAU	Gain	Gain,%
1.	Birthday Greeting Cards	503,685	+417,020	+481%
2.	La sfida delle città	388,877	+371,804	+2,178%
3.	ABC.com	766,426	+338,359	+79%
4.	Epic Fighters	430,771	+261,288	+154%
5.	Bar World	432,242	+228,551	+112%
6.	Profile Stats	721,875	+201,687	+39%
7.	Happy Hospital	484,805	+188,774	+64%
8.	OyunPark	236,952	+186,326	+368%
9.	Mighty Pirates	434,894	+163,373	+60%
10.	寵物戰爭	166,423	+155,237	+1,388%
11.	Puzzle Saga	210,387	+148,001	+237%
12.	Clash of Kingdoms	468,617	+139,398	+42%
13.	The Smurfs’ Village	309,430	+122,038	+65%
14.	Prizee Jackpot	845,943	+121,757	+17%
15.	Entrevista Social	192,284	+118,504	+161%
16.	FameTown	551,854	+117,354	+27%
17.	MyGame	400,602	+115,300	+40%
18.	MySpace	633,076	+113,953	+22%
19.	Quotes Factory	310,917	+113,158	+57%
20.	Little War	422,029	+112,319	+36%

Birthday Greeting Cards is not a particularly impressive app, with a very basic interface and card options. It also uses a tactic to convince users to buy its virtual currency, BdayBucks (Update: Socialsoft emails to say that the friend activity stream was working incorrectly; it has removed the feature.). See the right-hand side of the below screenshot, in which the app falsely claims that friends have recently bought currency. (None of those friends have even installed the app.)

La sfida delle città is an Italian-language geography test / game. It’s followed up by ABC.com, which is just showing a count of how many Facebook users are logging into ABC’s website with Facebook Connect. Such “apps” are becoming more common in our rankings; at number 13, for example, The Smurfs’ Village simply lists Facebook logins to a Capcom mobile game, and at 18 MySpace shows the recent Facebook integration to its competitor.

The really interesting apps on the list are the games, starting with Epic Fighters, a new text RPG from Digital Chocolate and moving down through some pretty good titles like Happy Hospital and Mighty Pirates. We’ll discuss all of those in more depth this morning over at Inside Social Games.