TweetDeck has recently released a .26.1 version, which includes, among other things, syncing your setup with the server, which also facilitates their new iPhone version, which you can sync your desktop setup down to the iphone. A neat card like (like the Palm Pre's UI) interface, which you can flip through nicely.
The only downside is a) I just bought Twittelator Pro and b) some of the input and message functions are different that I'm used to. Still a great app though.