To be honest, I kind of think Microsoft's "core" lineup for this year is pretty much set. Crackdown 2 is probably being pushed to fall though, and they'll probably also pick up Kingdom Under Fire II. E3 will just bring the Natal lineup from Rare/Lionhead/etc, which may have some more traditional titles mixed in admittedly. I think they'll have Gears 3 for fall 2011 as 360's big sendoff.
Out of Sony, I think we'll probably see a few of those rumored titles (Resistance 3 and Twisted Metal are all but confirmed already), but I doubt they have an onslaught of new stuff... if they did, they wouldn't have delayed GT5 into the period. I also wouldn't expect much out of Japan, SCEJ has seemingly atrophied this gen with the balance of power shifting to the Worldwide Studios. I do think we'll see a new Hot Shots Golf for Move though. A lot of the Move games seem to be PSN though (which Ape Escape is btw).
Nintendo's pretty easy to figure out (Zelda, Wii Relax, Xenoblade, etc), but they may have a surprise or two (Kirby, Retro's game, Project Sora's game, etc). The biggest surprise from Nintendo this year imo, is how they're positioned to utterly dominate Q2 (with Galaxy 2 & Other M) and how "hardcore focused" their lineup actually is (Sin & Punishment 2, Moster Hunter Tri, etc).
