I was very impressed with the Natal demo, but that was mainly due to Milo and the fact that Steven Spielberg and Peter Molyneux had just made an appearance. And that was before the $199.99 price was announced.
As it stands, the PS Eye can currently offer much of the hands-free control that Natal showed. With the correct software it could do facial recognition and can already do voice recognition. So you could have the option of logging into PSN automatically and navigating the XMB totally hands-free, which is very cool.
When it comes to the actual games however, the PS3mote gives totally accurate 1:1 tracking, whereas Natal doesn't. The idea of not having any controller sounds cool, but I don't beleive it can work. People still need to have a connection to a physical object. Consider the following two examples:
1 - Baseball/Cricket game. So you have the option of holding nothing (which will feel odd) or something to represent the bat. If you're going to be holding something anyway, surely you may as well be holding something that's going to give 1:1 accuracy. As we saw from the Sony demo, they can overlay bats, guns, golf clubs, whatever on screen.
2 - FPS. You can move 360 degrees, crouch, jump and aim but how do you propose you move your character on the x and z axes? This isn't a Star Trek Holodeck we're talking about here. So you still need some sort of controller in your hand to move your on-screen character about, may as well use that controller as the gun and have true 1:1 accuracy.
Now there are some styles of game that you could do totally hands free, but the above examples show that some games still need a tangible controller option.
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