I did work with the Kinect. For my senior design project in college I worked with a team of 3 to make a public gaming platform. Basically, each location would be a kinect and a projector. When a pedestrian walked up to it, they could start a game. It would do matchmaking with other public locations. The interface was all Kinect driven.

• We had a game of pong. When you have to run back and forth as the paddle, pong is SO much more fun. This mainly just scaled/capped the x and z location of the player, so it was pretty easy through Kinect. The game also had some random easter eggs when it detected certain poses.
• We also had one where you were on a railroad cart (the manual ones where you have to push up and down to make it go). A card would show up with a picture of a person doing a pose. As soon as you did the pose, your character would push down making your car go forward. You and your opponent had to race to do the gestures on the card as fast as possible to win the race. This was everything from jumping to disco dancing. For this, I actually just wrote a trainer that used a decision tree and I demonstrated each pose for the system. So, adding a new pose was just a matter of demonstrating it a bunch of times.
• We did the presentation of the project itself using a slideshow app we made that was also controlled by Kinect. The main interesting thing here was that we had to come up with gestures that we wouldn't do while talking or taking questions. ... We went with all or nothing. If both hands are above elbows or both hands are below elbows, all input is ignored. If one hand is down and the other is above elbow, we'd watch for signals.

Everything worked pretty well. This was the original Kinect years back, so there were some distance concerns and we had the challenge of keeping the excited onlookers from getting too close to the demo.