Anybody pick this up on a whim and try it?

If I had to generalize my girlfriend's gaming habits, it would include a) zombies, and b) rhythm games. So this title seems tailor made for her. IGN gave it a 5 and GameRankings gave it an average score of 51%, which isn't being too kindly. And to be honest, I'm not expecting Fallout 3, or heck, even the first Rock Band. I was just wondering if anybody here had any first-hand experience with it. Thanks!