Though the game only recognized one player's moves, whenever someone broke out Dance Central at a party, invariably someone else joined the fun. Multiplayer, therefore, was priority No. 1 for Dance Central 2, and is the most notable feature of a game that still gets the best of the Kinect.
A second player may drop in at any time in the game's quickplay mode, shown to me in the Kinect booth at E3. Either one of the dancing duo can drop out, and the game will switch the remaining dancer's character to the lead.
While there are dedicated multiplayer modes, this one-the-fly join-and-leave feature is the one best attenuated to how many people will play the game.
In multiplayer, last year's Dance Battle is augmented this year with a simultaneous dance-off that will feature handoffs to solo dancing as well as breaks for freestyle dancing. Freestyle gets a new look in Dance Central 2, rendering your figure (as recognized by Kinect) in a sculpture comprised of thousands of blocks. New environments and characters are included (I saw a beach bonfire scene) and familiar faces (I saw Emilia) also return.
For singleplayer, the game's Break It Down tutorial has been remodeled to focus on moves and tempo; players may speed up or slow down the move as they learn to master it at their own pace. A campaign mode returns, but the Harmonix team wasn't going into detail about it yet.
The new disc will ship with 40 songs and, as with all Harmonix games, will allow you to import any original Dance Central DLC and songs (provided you have the disc, in the case of the latter). That's necessitated new sorting options to get players to the style of song they're looking for.
Though structurally it looks the same as the original Dance Central the simultaneous multiplayer support is a necessary advancement and one the game handled seamlessly in the demonstration I was shown. The game will arrive in Fall 2011.