From what I know so far we have France, Belgium, Poland, Hungary, Russia, 2 US guys and 3 from Germany. But that's just the coders/designers.
A "1st world congress of UFO:AI developers" is a nice idea, but keep in mind that someone who can write english pretty well is not necessarily able to *speak* english fluently. So we might end up sitting side by side chatting via our laptops LOL.