Kinect/Project Natal?

So far I love the Kinect, though looking back at the original trailer for what at the time was called "Project Natal" it makes me wonder why they took out so many of the features they originally had. It does have voice commands, it does everything it said it would and your body is the controller, though things like video chat is different, it doesn't scan, it has face recongnization though not in the extent of this video below and it doesn't turn on and off with voice or let you scroll through features the way I thought it would. Until today I didn't even think anything of it, but then I saw this video once again that C.J uploaded way over a year ago and wonder why it has changed so much? See for yourself...

https://www.youtube.com/watch?v=5i5TvQ1RxLM