PS3 and Xbox 360 Tekken Tag Tournament 2 will have over 50 characters

While the arcade version had 44 characters, the consoles version will have over 50. The biggest in Tekken history.
There's also a new Fight Lab mode, exclusive to PS3 and Xbox 360. In this mode, you build up a robot. You'll have to play mini games and engage in boss fights. Clear these, and you'll get parts which can be used to customize your robot. Eventually, you'll end up with a robot decked out with parts and skills to your liking.