Halo ODST was an expansion to Halo 3, But the Hype from a Halo 4 announcement would kill the sales of Halo: Reach, only way to save it would be to add a Halo 4 beta to Halo:Reach, even so it is very unlikely especially since Bungie is gone and 343 Industries is taking their place.

Just wanna say insomniac is going to show a new ip at E3 calling it here!

I like your predictions. Anyway here are mine :

Sony

- PSP2 Annoucement
- GT5 + Release Date
- Move + Pricing + Release Date
- Agent + Trailer
- Killzone 3 + Trailer
- Infamous 2 + Resistance 3 + LBP2 + Last Guardian Gameplay
- New Ip's

Nintendo

- Zelda Annoucement + Trailer
- 3DS
- Vitality Sensors + Games
- Epic Mickey + Gameplay
- Wii Play 2 + Gameplay
- New Mario + Screenshot

Microsoft

- Natal + Release + Pricing
- Natal Games
- Gears 3 + Gameplay
- Halo : Reach + New Trailer + SP Gameplay
- Fable 3 + Gameplay
- Slim Xbox 360 + Price Cut
- New Ip's

This is my take on what's going to happen.

DEFINITELY HAPPENING:

Nintendo:

- Zelda Wii
- 3DS Mario game
- Video of pokemon black & white

SONY:

- GT5 trailer
- Infamous 2
- Killzone 3
- PS move
________

I hope:

- The Last Story trailer
- FF versus 13 trailer + gameplay
- Elder Scrolls V

Hmmm

I don't really care for anything other than I hope so I'll do just that.

FF versus 13 trailer a new one featuring gameplay, and I want it dated... but that probably won't happen, because it'll be dated in JPN first
Kingdom Hearts 3 announced with a trailer of something, on any system, but xbox360 or PC (For the main fact that it won't sell well and I love that franchise)
Zelda Wii
Xenoblade Release Date announced for US
Last Story, Trailer. And extra hope, Dated
Mass Effect 3 (Didn't they say it was going to be released on a shorter cycle (maybe good or bad))
Dragon Age 2 Announcement :D