According to NPD, Dance Central is the best selling Kinect game in USA and ranks on #11 in overall sales for the month of November.

However, Kinect Adventures did sell 2.5 million units globally but the sales are not representative as it came bundled with the Kinect sensor. The second best selling Kinect game was Kinect Sports and the third best selling Kinect game was Your Shape: Fitness Evolved.

Source: Joystiq.