I wish, as odd as this may sound, that they announced brand new IP's from both Rare and Lionhead. I'm not a huge Microsoft fan & they don't have the exclusives to lure me to Xbox, but they were very close with Viva Pinata and Fable (both of which I ended up getting for PC instead). Although they're both not the studios they used to be, I still think they have it in them to make great, unique games - and that would be a selling point of their consoles for me a lot more than Kinect/Halo.
Although, E3 isn't really aimed a people like me on the fence about buying the console, really, so I guess it's not too important what I think!