Hi everybody!
your project looks awesome and it gives me confidence to use TG2 but I'm going to comment anything about the architecture:
Twisted is great, but forces you into callback hell. In change, pyev [1] is cool, or you could be more interested io Tornado [2], the scalable, non-blocking web server that power FriendFeed.
[1] http://code.google.com/p/pyev/ [2] http://www.tornadoweb.org/