@Zerutreck: it can detect up to 6 people at a time with 2 skeleton locks.  Knowning a set of data is a person is basically tracking.  You know those data points belong to that person.

6 people in the field of vision is a lot, believe it or not.  Back with beta 1 and testing out tracking, having 4 people in my office was tight.

Have you played with the SDK?