This review is for the PS3 version of this game. The game is a lot of fun to play and everyone has a great time playing it. But the motion sensing of the game leaves a lot to be desired. For e.g. one of my friends decided to mess with the system and was literally flopping and flailing around with the Move controller in his hand and in the end got a higher score than any of the others (some of whom followed the lady's moves exactly). Moreover while he was continuing his buffoonery the lady in the game kept saying, "Great job", "Nice hip movement". It was a lot of fun from a party's point of view but clearly the game needs better motion tracking.
That being said, if you want to get a good workout then this game is really amazing. It has me sweating a great deal by the end of the 20 min workout (and I am one of those people who rarely breaks a sweat). My legs were really sore after the first time I did it. These dance workouts are amazing for your legs and arms. I could barely lift my arms (the first time) as I got to the last section of my workout. I also like that you can completely customize the workouts for months at a time.
All in all a great game if you are serious about your workout and try to imitate the lady as closely as possible, but if you want this as a competitive game for social gatherings then beware that the party clown will walk away with the firs prize.