Its pretty cool as far as I can remember,but it has been a long long time since I actually played.
I was going to freshen my memory a bit and play it some but I let my brother borrow my ps2. *fail*
I think its a lot of button pushing with simplistic patterns that make certain moves. There are a lot of different characters though, each with his or her own background that adds to the over all story line. You have to play each character all the way through in order to get all of the pieces. It really is a game that was made for people who liked story lines too rather than just action.
In its entirety, though, its a relatively easy, but still fun, game.