I'm not a huge fan, but that being said, its more fun and addictive than it looks.
kind of like tetris, it seems simple yet requires complete focus. Its funny because I can play a "complicated' FPS game with 9 buttons/triggers and two thumb-sticks and yet still carry on a conversation with other people in the room, but pressing 5 color-coded buttons to music seems to take total concentration and drive me frustratingly mad