The new PS3 motion tracker thing actually looks great. It's just like what everyone though the Wiimote was going to do before they realised wii motion control basically just meant "SHAKE THE CONTROLLER FROM LEFT TO RIGHT TO DO SOMETHING!".
Also the PS3 is capable of half-decent graphics and physics which is a big bonus for tech-fags like me.
http://www.gametrailers.com/game/playstation-3/2185
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The Microsoft Natal thing looks awesome for general UI interaction like in the video where they skip though DVD covers or use voice/face recognition (no more losing the TV remote!) but for games it looks rather shit (I know they're just example concepts, but the PS3 demo impressed me more simply because they were live demos not "hey look what someone might be able to do but probably wont"- type demos).