This is a sample from the K4W community. Josh Blake, K4W MVP, built an application that allows you to play the role of a broadcast meteorologist and puts your image in front of a live, animated weather map (all without the expensive green screen equipment).
This video (part three) provides a quick walkthrough of the important parts of the source code for implementing background removal. Check out part one which shows how the application works and talks about the key features. Part two walks through the important parts of the code for implementing gestures.
Full source code is published under an open source license at http://kinectweather.codeplex.com.