The BBC has a really good interview here which is well worth watching. And I must admit that the more I read and think about this, the more impressed I am.
The Wiimote will now be seen as interim technology, a side story on the road to the whole body interface. Having face (and emotion) recognition in Natal is a big step forward with huge gaming potential. Allied to the whole body scanning and voice recognition we have something that is of groundbreaking importance.
Sony (SNE) is rumored to have a PS3 gesture interface announcement later Tuesday. If it does not measure up to Natal they are in even bigger trouble than they were already. And the Nintendo Wii looks very previous generation now, sales will surely take a big dive, even with the inevitable steep price reductions. The announcement of SuperWii will be as soon as possible. The Xbox 360 could yet become the best selling console in this generation.
Natal has immense possibilities way beyond recreational gaming. Sports coaching, medical rehabilitation and military training spring immediately to mind. In fact any human activity where you have to build neuromuscular facilitation.
The limitations put on the human imagination by previous gaming interfaces have all been swept away. A lot of clever and creative people are going to do a lot of clever and creative things with Natal.