Heh, yeah take part in gb... STM has had tens of offers maybe even hundreds, of which he's accepted none to my knowledge. You'll also see a lot more of trinity in a few weeks when it becomes official.
As to London, I think really unless you can get a few map modders to start you off that it hasn't got a chance, mods always look much better when there's screens rather than just words. And as most of the vice city mod were stm's cars most of which were rejected versions of ones that will be used in GB, it doesn't say much