Just Dance 3 doesn't stray from the tried and true formula too much, but there are some nice additions. The main one for me is that there are now unlockables. These are earned from accruing stars after playing through a song (one through five depending on how well you did). The unlockables include some new songs, as well as some medleys that splice together different moves from various songs, including songs from the previous two games in the series. It was fun to see these throwbacks to the previous games, and having alternate choreographies to a song is a nice way to add a little more gameplay to the package. The game also adds 4-player choreographies, "Hold My Hand" choreographies in which players literally hold the same controller, and some basic achievements. As is par for the course some of the achievements are downright tedious and a lot of them revolve around the multi-player dances, but for gamers like me it's a nice minor addition.
I don't know if it's just me, but I found the game to recognize my movements pretty well in general. It may be that the movement detection is either better or more lenient, although I suppose it's possible that I've just learned how to match my movements to what the game wants. I got a 5-star ranking (the highest possible) on a decent number of songs, although the songlist itself was pretty similar to the previous two games. It would be nice if they shook things up a bit with other genres, such as classic alternative rock or folk music. Still, the extra features probably gives this the edge over Just Dance 2, but the differences are pretty minor. I don't expect subsequent sequels to evolve much either, but it should come as no surprise that I'm planning on dancing my way through them anyway.