TweetDeck just went public on the Android Market, you can grab version 1.0 now via our QR-code link below. What's new in the official release? Probably not much aside from bug fixes. You can expect all the features of the last beta, plus automatic updating (for those on the new Market). Here's a video:
TweetDeck has also hinted that later releases will provide landscape view, more Facebook integration, and better support for multiple accounts. And yes, it's free.