Overall I'd say Sony's conference was the most enjoyable to watch just because of Tretton. I like that guy. Probably the only PR guy I've ever seen at E3 that seems real.
Content wise, I'd say it's a toss up between MS and Sony. MS had the whole Netflix thing, 16:10 support, total dashboard overhaul, avatars, full game installs, Gears 2, and of course FFXIII while Sony had LBP, Infamous, Fat Princess (!!!), tv/movie delivery service, and Resistance 2. Seems like a wash to me.