E3.net under the E3 Games tab. There's just one problem ... E3.net isn't the official E3 page. (If you're curious, here's the official site.)
Take note of the top banner, the bottom collection of links and all the latest news posts: yep, it's an UGO site. We've put in a call to their PR to see if there's any affiliation with the media summit, but that said, we doubt Microsoft, Nintendo, Valve or id Software would ever let these high-profile games be revealed so unceremoniously. Chalk this up as wishful thinking in the meantime.