It has been legal in past years, but that is no guarantee as to whether or not it will be allowed in future years. I believe they banned the use of colored cards n autonomous in ftc....but I could be mistaken.
As FrankJ pointed out, cheesy vision did not require a kinect, it was a brilliant and simple solution to the problem. The reason you use a kinect for gesture recognition is because of the kinect's depth map.
If you want something to play around with, a brilliant freshman on our team this year wrote this up one night:
http://www.chiefdelphi.com/forums/sh...d.php?t=129910