There was a recent conference in London – “WarbleCamp” and it attracted developers from all over Europe to meet with Twitter, specifically Raffi Krikorian of the Twitter API team. It was here he presented about the Twitter Annotation feature or “Twannotations.”
Some slides from the presentation can be found here.
Another annoucement, met with mixed feelings, is that Twitter now has their own Android Client, to rival Tweetie on the iPhone. With Twitter themselves moving into the developer space it begs the question, what kind of a message does this send to developers? As developers, it is a bit scary to think that one can spend a lot of time on an app just to have Twitter come in and make or buy their own version. Although, the possibility of being bought isn’t so horrible 
