We've been using the Tweetbot for Mac alpha for several weeks now. It's about time that a more polished beta version arrive, we'd say -- and the new 0.8 revision does its best to justify moving one letter up the alphabet. Most of the upgrade focuses on improved multi-column and keyboard support, along with a heap of bug fixes. The real story, though, may be what Tweetbot can't do. Twitter's tough new API
