I see that both the Register and Darknet web sites have posts up about a piece of software called Vibe (by Zami.com) for anonymous tweeting.
One problem is it is an iOS App, so it may not last long if Apple pulls it.
Is TAILS thinking about or planning to do anything regarding this capability (an anonymous tweeting social media app) for TAILS in future releases?
Is there anything preventing you from registering a Twitter account within Tails using Iceweasel and then start twittering?
Side note: This new trend of "one application for every website" isn't a very progressive one in general, and for anonymity in particular. More code implies more bugs and security issues. OTOH, such an application designed to be anonymous from scratch may perhaps be good. Perhaps. A much better solution would be a web browser designed like that, of course.