E3's getting pretty close. Just realized it's only a bit over a week away. Can't wait

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Ok, overall guesses on current info -
Nintendo -
3DS
Zelda, Metroid, and the new Pokemon titles actual gameplay will be shown.
Microsoft -
Microsoft will go for a rebranding of the 360 in a sense. The leak about new game cases, a slim 360, and Natal being treated like a new console launch. I think that coupled with a price drop will make Microsoft's goal this E3 be making the 360 feel fresh again.
They'll probably use some tricks from the past as well. Show off multiplatform titles like they were exclusive (Dead Rising 2, COD Black Ops, and a few others), and pull out another 'shocker' by showing off another PS3 exclusive. I'd guess with the recent interview from the Square president, and his attempt to clarify being even more iffy, that FF Vs. XIII will be it.
Finally they'll finish up with Reach, and Gears 3 gameplay. Also I have a feeling they may show off Crysis 2 to try and steal the thunder from Killzone 3's announcement on Sony's show.
Sony -
I'm not sure what to expect anymore lol. The things I thought they'd save for E3 as their big shockers have been revealed pre-E3. So what could be a bigger shocker than Killzone 3, and LBP 2. I'm going to guess it ties into the rumor that was, "as big of an announcement as when Sony announced GTA San Andreas as a timed exclusive".
Beyond that, DC Online, FF XIV, Killzone 3, LBP 2, Last Guardian, Socom 4, Gran Turismo 5, and a few others are all shoe ins. Twisted Metal is possible, but not probable. A Starhawk rumor is persistant as ever, as is inFAMOUS 2, and Resistance 3. A Jaffe game is supposed to be being worked on that contains 'fantasy, and action'. Possibly Free Realms (as possibly that kiddy Star Wars free MMO Sony are making), tho I could care less about it.
Move and a more detailed look at it's games being shown is a no brainer. I also buy the rumors of a PSP2 being shown. So PSP2 will probably be to this E3 what Move was to the last one.
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Pointless rambling about Vs. XIII
Now with that said, even tho I'm predicting that Vs. Xiii will be shown off on MS's show, I'll be pissed if it does. I'm fine with 360 owners getting to play it, but this would be two times Square did this this gen. Saying that a FF is exclusive for almost half a decade, then debuting it on Microsoft's show. Especially now considering how XIII sold 4-5x better on the PS3 overall to allow MS to rub it in PS3 owners faces. I was looking more forward to Vs. XIII than XIII itself, and this ones upsmanship we took your exclusive crap gets incredibly annoying when it happens every year. Vs. XIII is supposed to be shown at TGS, so I do see it as possible that MS shows it's trailer to steal the thunder, then Sony gets their chance at TGS to show gameplay.