I care as much about Project Natal (and I don't believe a thing Peter Molyneux says anymore, so I will believe that technology when I see actual users trying it out) as I do about Nintendo's Pulse Monitor or Sony's mo-capping. That is to say, not at all.
Of those three, the only one I can see being used for gaming is Sony's, and even then I think it's of limited efficacy. Natal may be nice for educational software (great, in fact) but not for gaming.
I care about one thing at E3, the games. Sony had the best showing for games, therefore Sony impressed me the most. Microsoft's highlight for games was the Metal Gear Solid game that is multiplatform anyway. I'm sorry, when your highlight for TWO E3s in a row is that you are ALSO getting a game your competitor is? I just don't care. Showing Rock Band Beatles and Metal Gear Solid: Rising on stage as your highlights, when they are games that are on other platforms as well, is lame.
Nintendo had Metroid, but not much else (Though that does look awesome).
Sony had ModNation, God of War 3 (Disappointed me, but still looks good, not great), Uncharted 2 (Best looking game I've ever seen, easy), FFXIV (arguable, since it's on PC too, but so were all MS's exclusives, so I'll list it here), APB, MAG, and a few others.
Microsoft showed cool technology, yes, but motion-capture is NOT the future of video games. I don't want to steer a car by moving my hands in the air like a ninny, I want an actual physical wheel-controller. I'm not going to navigate RPG menus by pushing at virtual menus in the air, I want an actual controller. The only uses i see for motion-capture stuff (this goes for Sony and Nintendo too) are sports games really, and educational software. If motion-capture becomes a standard for video game interfaces, I'm probably just going to stop gaming, because it isn't fun. (I have a Wii, it has it's niche games, but the best games I have played on it used the motion-capture barely at all, like Paper Mario or Mario Galaxy).
E3 is about the games, and Sony is the only one that really impressed me there.
EDIT: Doh, I forgot The Last Guardian, one of the most impressive games of E3, oops

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