iPhone OS 3.1 is now available for download through iTunes. 
At today’s “It’s Only Rock and Roll” event Apple has announced the release of iPhone OS 3.1 for iPhone and iPod touch users.
The iPhone 3.1 update, which is free for iPhone users (and for iPod touch users who already have the 3.0 OS) adds a much-requested feature, Genius Mode for the App Store. Now the same technology that recommends songs will be used to recommend applications. Hopefully, this will make navigating the App Store and finding more gems easier than ever before.