I have a 4 year old boy and he is in love with this game. He even said loud "this game is awesome!" And he is playing it all by himself on easy. The wife and I are watching TV while he is in my gaming area eating it up. I only got to play the tutorial, he is hours into the game.
It looks fun anyway!
$400 purchase vindicated for the pure fun he is having. After he falls asleep tonight maybe I will be able to play the system...