The kit its self is amazing although their is a minimum height recommendation of around 40 inches (1 meter / just over 3ft) so younger kids won't register correctly with the censor.
I keep seeing people talk about lag, I've not noticed any lag, in fact its very responsive but I think thats down to the fact that I took a little more time to make sure it was calibrated correctly. Our room lighting isn't bright, but it lights the place up and I imagine the lighting also has an affect on how responsive the device is.
If you've calibrated and lit your room but notice some lag, try closing the curtains because perhaps there is some other light affecting your Kinects sensor.
I thought more about how this could be better and some kind of button control for FPS and similar, perhaps a glove control like in Minority Report?
I'm impressed, I love the Wii and I'm an old school Mario fan, but this tops it. Joyride is comparable to Mario Kart.
I just hope there are a lot more innovations and games to come. :-)