"Whatever is going on in the new Kinect Microsoft unveiled recently, it’s doing more than its predecessor. It appears vastly more precise, smarter about telling people from objects, better at telling people from other people, and more responsive to gestures."...

"For Kinect 2.0, it’s power + USB 3.0."... so you will need to have a usb3 port... well... such is life I guess.   ;)

The link below from Microsoft describes in easy to understand laypersons terms, the new developments.

The new sensor includes a high-definition (HD) color camera as well as a new noise-isolating multi-microphone array that filters ambient sounds to recognize natural speaking voices even in crowded rooms and expanded field of view. The methods used for Skeleton tracking and Infra Red arrays have also been completely redesigned from scratch. 

"The new sensor tracks more points on the human body than previously, including the tip of the hand and thumb, and tracks six skeletons at once."