Easily the biggest new feature though is online play. There are only a handful of match types, but you can create custom matches, a friend rooster, and view leader boards. Miis feature too - you can have one representing your character along the top of the screen. Their eyes pop out amusingly every time you take a whack.
If a confused elderly person bought you this for Christmas instead of World at War it wouldn't be the worst Christmas ever, although you'd still be better off buying some WWE DVDs and practising the moves on your little sister. Ignore her screams - she loves it really.