Later today, social browser RockMelt will roll out its first major update today, adding a Facebook Chat bar, an Instapaper-esque “View Later” option, and deeper Twiter support. It also runs on the latest Google Chromium 10. The new features bring RockMelt Beta2 closer to becoming a full-fledged replacement for leaving a window of these services open at all times.

RockMelt first launched in November of 2010 with the goal of building an internet browser with social baked into the chrome, allowing users to access much of their Facebook, Twitter, and bookmark functionality without visiting a URL. Instead, notifications for wall posts, @ replies, blog updates and more are pushed to RockMelt as alerts, eliminating the productivity-fracturing process of checking each site manually.

There are several deficiencies in the product’s Facebook integration, though. Users can’t see Facebook’s relevancy sorted Top News feed or activity stories about friends, just the real-time feed of full stories. The status update publisher also doesn’t let users edit the caption of a link’s preview. Still, for those wanting real-time social updates, RockMelt has a lot of promise.

The social browser’s Facebook Chat already had some advantages over the canvas site, including the fact that photos and videos linked to would appear in-line. It was one of RockMelt’s most popular features, with users Chatting an average of three times a day, but users requested a better way to Chat with multiple friends at once. Now Chats can be parked as tabs in the bottom Chat bar of Rockmelt Beta2.

The Twitter improvements include the ability to edit  retweets (something annoyingly absent from Twitter’s website), read direct messages, reply to all users mentioned in a tweet, and simpler Twitter search.

View Later makes it easy to favorite a Facebook update, tweet, or URL that users didn’t have time to experience. The option, quite similar to Instapaper, improves on traditional bookmarking by making important items easy to consume and then delete, allowing saved content to be accessed from anywhere users log in to RockMelt rather than trapped on a single machine, and enabling users to save social media content in addition to full websites.

The update won’t be available for download until later today, so we can’t tell exactly how smooth the flows of these new features are. In concept, though, the Chat update will make RockMelt Beta2 a viable Facebook substitute for those carrying multiple conversations at once. View Later for Facebook updates adds something unavailable on the canvas, and could be especially helpful for pulling longer form content such as videos and news articles out of the stream and saving them for when a user has time to consume them.

The Andressen Horowitz-backed RockMelt has combined both incremental updates and another valuable web service into the Beta2 release. Judging by the source tags on items published to our news feeds after RockMelt launched, users played with the browser for a few weeks but soon returned to their old habits. Time will tell whether these changes make RockMelt any stickier.