As mentioned here (in this thread), there's no reason at all why Japan's a "small nation" - other than that the game actually promotes a high level of turnover with nations that aren't on the large side. It's unlikely that Japan would ever be a 'big' nation, but it beggars belief that it's not in excess of 100 users.
I agree: it is insane.
http://with-malice.com/ - The half-crazed ramblings of a Lakers fanatic in Japan