I've been really slack about updating pytwitter. As a consequence, it mostly doesn't work as a result of twitter forcing certain requests to use GET requests only (previously, POSTs would work just fine for everything). Oops. Anyway, that's all fixed in pytwitter 0.3:
http://pypi.python.org/pypi/pytwitter/0.3. Right now there's a list of methods that require POST and if the method called is in there then it gets sent using a POST, otherwise a GET is used. Not perfect, but it's late.