Tweetbot is out and contains a ton of new features and improvements. Federico Viticci over at Mac Stories has a fantastic comprehensive review of the new version, but this particular feature caught my attention as I've wanted it for a long time:

Last, some minor touches in version 2.3 will contribute to improving usability and to allowing users customize their timelines to their needs and tastes: retweets from specific users can now be disabled at any time, and it’s possible to quickly open the last saved draft by holding down the tweet compose button. The timeline sync bookmark icon is now an optional setting, and Tweetbot is capable of uploading high-res images when on WiFi. So now those brief acquaintances of mine who I work with or are a friend of a friend who retweet Spa deals or topics I don't care about, I can block without having to go to Twitter.com to toggle that setting.