Any movements involving the hips would be considered sexual whether they would work in a sexual way or not. I remember watching some documentary about Elvis and apparently him gyrating his hips was a big deal back in the 50s.
As for Kinect or any similar motion thing, apparently neither Sony nor Microsoft nor Nintendo will allow sex games on their consoles, so a Kinect compatible sex game will never happen, sadly. The God of War sex was only allowed because it didn't show anything... except boobs which are apparently okay with an M rating, but not genitalia.