You could'nt ask for more
One of the great new things about this game is that you can transform, and you'll unlock each new form through out the game and these are the forms
Valor Form
Wisdom Form
Master Form
Final Form
and the reason you can transform is because in this game you are given some magic clothes and sometimes you'll transform in to like a Heartless looking form but I'm not sure why, but I've heard that only happens when you over use the Drive gauge which is the energy you need to transform and for summons.
Now I wont fill you in on to much of the story because that would probally ruin it for you if you get this game but I'll tell you that at the beginning of the game you'll play as a boy called Roxas, that for some reason is a key blade wielder, but not just that, the key blade he uses happens to be the same one as Sora's but in time you'll find Sora sleeping in a chamber and you wont see Roxas again until later in the game.
Theres also a new combo where the triangle button comes u on the screen now and again for a reaction attack but it's othing special and not that hard to do, so dont look forward to a brand new combat system because it's very similar to the one in Kingdom Hearts.