Depends who bundles the better game with the product. Got to say, sounds like Nintendo might have an advantage there but I wouldn't be surprised if MS bundles a pretty big game with Natal that takes off. Can't talk to much about the Sony motion controller as really they haven't stated much about it or really been hyping it that much. Really starting to doubt if they are going to be able to release this this Spring. But if it doesn't come bundled with a game, and more than likely needs to be a new release, then it won't take off that well.
So right now I'm going to go with the Vitality Sensor and Natal being about dead even and the Sony Motion controller being not as close. But this is a little too early for me to really know. We'll see how all three plan to release each new product and then go from there.
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