God of War III is a 2010 title. MAG, however, should hit this year. Around the holidays, I believe.

I think there are a few scenarios for who might win.

NIntendo:

If they show off Zelda Wii, its clear they would win for me, and in general Nintendo fans would be freaking out. However, I have a feeling they'll wait until after Spirit Tracks comes out to show off Zelda Wii. Other than that, they'll probably focus on Spirit Tracks (possibly announcing a ST/DSi bundle), show off 1-2 core Wii titles for the '09 holiday season, and announce another big game in the "Wii ____" series for sometime next year. Maybe we'll see something from Factor 5 too.

Personally, I'd love either Pilotwings or Kid Icarus by them.

Sony:

Its already a given that they'll be showing off some sort of major PSP hardware revision. That certainly gives them an advantage going into E3. Plus, they need to finally unveil LBP PSP, possibly with some exclusive features that'll work with the new hardware.

What matters is what they'll show off in addition to that. They've announced most of their big ps3 line for up until March 2010, so we know they'll be announcing a couple more games for next year, and they have a number of studios who have been quiet for quite some time. They could show off Starhawk, or Twisted Metal. However, it has basically been confirmed that the latter will be officially unveiled at a standalone event. Or they could show off whatever Sony Liverpool's been working on. Trico is finally out of the bag, but the footage shown is near two years old. They may plan to give it a more proper unveiling at E3. Hopefully they'll make a big to-do about it, because imo Team ICO deserve the fanfare.

I also think they'll announce GT5 as their big holiday title.

And who knows, they may show off a motion controller, using something like a new Hot Shots game (either Tennis or Golf) to show it off. ;)

Microsoft:

Microsoft has a number of possibilities. Possibly third party titles going multiplat ala FFXIII, maybe more Halo stuffs. Personally, I think they'll announce MGS4+ as a 360 exclusive, with word coming later at E3 that the extras found in MGS4+ will be released as DLC for the ps3.

They may show off whatever cool concept Lionhead is working on, and I'm sure they'll show off a new game from Rare and Forza 3, both with holiday release dates.

I think the big question will be Rare's new title. If it's more Viva Pinata, people won't be very impressed. If it's something like Killer Instinct 3, or a re-imagination of Jet Force Gemini, people will probably be pretty damn excited.

We may finally see something about Halo Chronicles, too. And maybe that motion cam lol.

Overall:

Personally, I think that Nintendo has the most potential to do well, but they'll probably take their usual "we don't care what you think" attitude, and show off more Wii Fit, even though they certainly do have the goods we want hidden away at Nintendo HQ, being worked on behind the scenes. MS also has great potential to do well, but I have a feeling they'll think MGS4 going multiplat (and having the enhanced version only on their console) is something more than it is, and make that along with Forza 3 their big announcements, even though we saw both coming from a mile away. I mean, they've made much ado about nothing before. As for Sony, the new PSP could be big, or it could be horrible, if they remove UMD and add nothing else substantial to the mix. Assuming the PSP announcement is pretty good, then that and hopefully footage of Trico plus another 2010 title for the ps3 would probably put Sony on top (at least for myself).

My most anticipated games are Zelda Wii and Trico. Big announcements for either would have me bursting with glee.

I think Zelda is a bit over-rated. Not the game, but the weight on an announcement. It has to be a really good Zelda game, not just another Zelda game.

Microsoft won on the back of one Sony third party exclusive going multiplat. It was massive because it was so unexpected. Nobody saw it coming.

Nothing they can do now can match that. Versus XIII? People saw that coming. MGS4? People saw that coming. MGS5? People saw that coming. Haze, Valkyria Chronicles, Yakuza? Nobody cares.

As for "more great exclusives to reveal", let's have a first party studio comparison, shall we? The ones that people actually care about are in italics.

Microsoft:

• BigPark: Undisclosed Xbox 360 Games
• Lionhead Studios: Black & White series, Fable series
• Rare Ltd.: Banjo-Kazooie series, Conker series, Perfect Dark series, Viva Piñata series
• Spawnpoint Studios: A studio set up to develop future Halo video games since Bungie became an independent studio.
• Turn 10 Studios: Forza Motorsport series
• Xbox Live Productions: A studio dedicated to developing Xbox Live Arcade games and other media content.
• Wingnut Interactive: A studio set up in partnership with Peter Jackson to produce Halo: Chronicles in conjunction with Bungie.

Plus:

• Bungie: Halo series.
• Epic Games: Gears of War series.
• Mistwalker: Blue Dragon, Lost Odyssey.
• feelplus Inc.: Ninety-Nine Nights II, Lost Odyssey.
• Artoon: Blinx series, Blue Dragon.
• Twisted Pixel: The Maw, 'Splosion Man.
• Gastronaut Studios: Small Arms, Gel: Set & Match.

And Sony:

Japan

• Japan Studio – Ape Escape, Siren, LocoRoco, Patapon
• Team ICO – Shadow of the Colossus, ICO
• Clap Hanz – Everybody's Golf, Everybody's Tennis
• Polyphony Digital – Gran Turismo

North America

• Naughty Dog - Crash Bandicoot, Jak & Daxter, Uncharted: Drakes Fortune
• Santa Monica Studio – God of War
• San Diego Studio – NBA, MLB: The Show
• Sony Bend – Syphon Filter
• Sony Online Entertainment LLC. – EverQuest
• Incognito Entertainment – Warhawk, Twisted Metal
• Zipper Interactive – SOCOM: U.S. Navy SEALs, MAG
  

Europe

• London Studio – SingStar, Eyetoy, PlayStation Home
• Studio Cambridge – MediEvil, PlayTV
• Studio Liverpool – Wipeout, F1
• Guerrilla Games – Killzone
• Evolution Studios – MotorStorm, World Rally Championship
• Bigbig Studios – Pursuit Force, MotorStorm: Arctic Edge

PLUS:

Japan

• Level-5 – White Knight Chronicles, Rogue Galaxy, Dark Cloud
• Game Republic – Folklore, Genji
• Q-Games – PixelJunk
• Media.Vision – Wild Arms
• Pyramid – Patapon
• From Software – Demon's Souls

North America

• Insomniac Games – Resistance, Ratchet & Clank
• Sucker Punch Productions – InFamous, Sly Cooper
• ThatGameCompany – Flow, Flower
• Ready at Dawn Studios – God of War: Chains of Olympus, Daxter
• High Impact Games – Ratchet & Clank: Size Matters, Secret Agent Clank
• Eat Sleep Play – Twisted Metal: Head On (It's David Jaffe's studio)
  
• Slant Six Games – SOCOM: U.S. Navy SEALs Confrontation, SOCOM: U.S. Navy SEALs Fireteam Bravo 3
• LightBox Interactive

Europe

• Quantic Dream – Heavy Rain
• Relentless Software – Buzz!
• Media Molecule – LittleBigPlanet
• Ninja Theory – Heavenly Sword

So Sony's lineup is significantly bigger.

Microsoft or Nintendo - sony simply can't wit what they have right now. we basically know their whole lineup for next 6 month so how they can suprise us?
microsoft has a lot of announcements:
2 Rare Games,
new Molyneux game,
Gta4 second DLC episode,
new jrpgs from MS second party developers,
possible Crackdown 2,
motion sensing camera,
possibly new additions to Xbox Live and Marketplace,
Halo ODST, Forza3, Alan Wake, APB, new Splinter Cell,
maybe even that rumored handheld,
and probably at least few new games for second half of 2009 and first quarter of 2010.

nintendo has well way too much to mention everything. they can simply show gameplay videos from their preTGS lineup of games, give us few new announcements(Retro new game, Pikmin 3) and they will have best nintendo E3 conference in years maybe not best E32009 but definitely The Best Nintendo Show on E3.

oh and Kantor most of sony studios from your PLUS section aren't first party(they are either socond party or were making single exclusive game or franchise for sony and still are releasing games for other consoles).

Either Sony or MS, not interested in Nintendo. Sony will probably have the best new games announcements, they were the only one at E3 2008 to actually reveal new games (Not counting Lips/Wii Music from the other two). With the PSP Go and PS3 Slim also. MS's may revolve more around features, like the motion sensing camera thing and 1 vs 100. With 1 or 2 game announcements.

I think people are forgetting about Bungie. Halo 3 came out in 2007 and Halo ODST was only being made by a very small team. People expect that everything Bungie touches turns to gold, so any game they announce will be expected to be massive and its defianately unannounced and its definately a new I.P. Bungie is bigger than every Sony studio except Polyphony Digital at the moment, and we know what Polyphony have been doing for the last few years.

I think my list basically disproves the point you are making (Yes, I know the "plus" section are third party, that's why they are in a plus section. Same with Microsoft).

Sony had a lot of franchises back in the day, and few of them have made it to PS3. We have yet to play a God of War, Ico game, Jak, Sly, Twisted Metal, full WipeOut or Syphon Filter, and most of those haven't even been announced for PS3.

And how can you assume we know Sony's 2009 lineup, when you're saying Microsoft is going to announce more? We've already figured out that the "only Sony announces games early" statement is bullshit- Alan Wake and Banjo Kazooie: N&B were both released years after the announcement, while Resistance 2 and MotorStorm 2 were announced in 2008. Ratchet and Clank Future: Quest for Booty was released two months after being displayed at E3. I don't believe Microsoft has much history of releasing games four months after they are announced (Sony Japan, however, announced Demon's Souls at TGS in November 08, and released it in February 2009).

I can, in fact, counteract every Microsoft prediction you have with a Sony prediction.

2 Rare Games, Eat Sleep Play game, several other first party games
new Molyneux game, Team ICO game
Gta4 second DLC episode, GTA first PS3 DLC episode
new jrpgs from MS second party developers, New games of a variety of genres from all of Sony's second parties
possible Crackdown 2, possible Sly/Jak game
motion sensing camera, Same for Sony
possibly new additions to Xbox Live and Marketplace, New Firmware update, additions to PSN Store
Halo ODST, Forza3, Alan Wake, APB, new Splinter Cell, MAG, God of War III, Uncharted 2, A Crack in Time, Under Siege, WarDevil 3, GT5, and several more.
maybe even that rumored handheld, PSP2/PSP4000.

In sales, yes. But in interwebz popularity, they are about equal with Team ICO.

If we get a new PSP then Sony wins for me :P

And thb from a gaming perspective I actually think that Sony will win... they only need to announce GT5, GoW3 and FF13 ( japan) for this Q4 and we are good to go :P Of course Im certain that we will see other projects to ;)

MS... it will probably have a decent showing but Im not expecting any FF13 caliber announcements at this year e3... but they will probably show off a ouple of cool games.

Nintendo... well they will show off a couple of casual games, a new Wii zelda and a handfull of 3rd party exclusives. Nintendo fans will go wild about it, I will still consider it mediocre :|

I think Sony will win but Microsoft and Nintendo will still have some interesting stuff