Joining fujin = joining the little zerg.
This poll will show fujin to be less populated than they will be in game, as fujin are mostly little kids who like ninjas, and don't go on forums.
Edit: Faction with lowest master points can't jump ship to nangin. Sorry misschief
Plus, jumping ship cuz ur outnumbered is lame. Jins will be close to guans with the least, depending.