Probably can find a better list later, but here are my predictions/hopes for E3:
Microsoft:
I think most of their surprises are out (like 360 "slim"), expect to see a lot of Kinect. Don't follow them as closely as the other two (since I don't own an XBox), so no idea. I'd of course expect to see the next iteration of big franchises, and maybe a surprise "hey, FF14 is coming to XBox too!"
Nintendo:
I'm expecting a lot. Mainly, because the last few E3s have been a complete joke (I'm looking at you Wii Music/Cammie Dunaway/etc). Nintendo is losing some steam (but still way ahead in sales), but I think they know they need to step it up a bit.
My expectations:
* New Zelda, front and center. Lots of Metroid footage.
* 3DS, obviously. Might be time for me to buy a DS (holy huge RPG backlog, batman!)
* Bragging about sales; being smug about competitors' move to motion games
Expected Surprises (hopes, more like it):
* Wii HD
* New online service that isn't horrible (but probably costs money)
* New F-Zero please. Thanks.
I am not stating a probability for these guesses; but I am saying I expect the Nintendo conference to be a surprise. Guess I'll find out in a few minutes.
Sony:
Also expecting big things.
* Plethora of Move demonstration, especially in the FPS area.
* Release date for Gran Turismo Forever. Seriously, it's been shown at every E3 since the announcement of PS3. Wouldn't be surprised if it launches as a move title.
* More footage on The Last Guardian
* Announcement for Resistance 3, other new iterations in big titles.
* Lots of footage from FF 14
* Sales announcements. They've almost caught up to 360, and I would guess have already passed if you count the re-buys for RRoD.
Possibles:
* Wouldn't be an E3 without a new SKU or two. Add bigger hard drive + wireless N
* Premium subscription is likely. Have heard this would come with PSN game downloads, which would be very nice.
* Kevin Butler? (I know he's just a paid actor, but he still makes me lol)