Tweetie 2.1 [$2.99 - iTunes link] -- a FREE upgrade for Tweetie 2.0 users -- brings support for Twitter's new Geotag feature (so everyone will know where exactly you're tweeting from), Twitter lists (what lists you have, what lists you subscribe to, though not the likely less-wieldly lists you're on), and the controversial new-style re-tweets (where you see the original tweeter in your timeline, not the person you're following who re-tweeted it).
There are other additions as well: report spam (via API), tweet-stream "gap" detection (looks like a torn gap in your timeline), and a tone of other stuff (including disable pin-stripes for the pixel-haters).
So how does Tweetie 2.1 handle all this new stuff? With Atebit's trademark buttery-smooth UI. Geotag is a new icon under the tweet-count drop-down menu. Twitter lists can be accessed via the More (...) icon on the bottom navigation bar, and you can view, manage, and even add new lists right on-device. New-style re-tweets get a small pink corner icon on the top right, and tapping on it brings up the original tweet with text on the bottom telling you which person you follow re-tweeted it.
If you decide to give it a try, let us know how you like it. (Or help me try it out via @reneritchie)
Screenshots galore after the break!