Microsoft
After 3 lackluster E3's in a row, I hope Microsoft tones down the "Kinect Kinect Kinect!" hype. I expect them to make a HUGE showing for the Xbox 720/Durango, with the usual Xbox Live Arcade/Gears/Fable/Forza/Halo announcements. Also, more non-gaming apps and media services. Yay.
Sony
Sony will abandon the PS Move's "WonderBook" series and will go back to pumping out more Uncharted, Ratchet & Clank, and God of War games. Then they'll try to prove that the Vita isn't dead yet by signing more exclusive deals with 3rd-party publishers that don't give a **** about Sony's handheld investments. And PS4/Orbis will be shown in some form.
Nintendo
Nintendo will FINALLY announce the Wii U's Virtual Console service, and every existing VC game that is already on the original Wii will be downloadable on day one. The Wii's "Vitality Sensor" will be brushed aside like it was never announced, and Nintendo will instead integrate that tech into a redesigned Wii Remote. Smash Bros. 3DS/Wii U, 3D Mario Wii U, 3D Zelda Wii U, Zelda 3DS, Pokemon 3DS, and a new Metroid Prime game will all be shown. Nintendo Network will be expanded to 3DS, and the eShop will become available for use on web browsers and mobile devices.
Apple / Google
Just kidding. They don't care about gaming enough to show up at E3.
Microsoft
Its going to be all about the Durango but don't expect the usual players there. Halo 4 took four years to come out and it was built from the reach engine, Frankie confirmed that the next Halo game is being built from the ground up so don't expect halo 5 for at least three years. The closet thing to expect is Spartan Ops season 2.
So far what to expect from Microsoft is.
Durango unveiling And Kinect 2.0
Spartan ops season 2
New IP from Tequilaworks made from unreal 4
New IP from epic based on the 3.9 demo and a fortnite port.
Alan Wake 3 from Redemdy (worst kept secret)
Forza 5 or PGR4
Twp new rare games
Ryse from cry tech
Game by Ruffian games
New IP by black tusk studios
Tease of the Microsoft studios Vancouver game
Tease of what every project the naughty dog and irrational guys are working on.
Fable IV as well as a new IP from lion head
Next connected TV game by Soho productions
Going to see a bunch of non gaming features and home automation stuff
Third party next gen stuff
Twisted pixel next game
Kinect sports 3 by BigPark
Live takes a massive dump over PSN and NN feature wise
Also how do you define lackluster. Like change Shane shatterfield said last year while he found the Microsoft press conference to be the worst of them all and didn't focus on games or new IP it didn't mattered. All of the non gaming journalist from (CNN, abcnws, the verge' etc) were blown away and were far more receptive too the stuff like smartglass, and usher. That was evident in the posts around E3 were Microsoft while getting panned by the games media had a lot of good buzz from mainstream media which gets way more traffic. Yet these same mainstream sites had little to say about Sony and though the Wii u was still an add-on.
Sony
Not really sure what they will do with the vita tanking and internal PS3 development still going on.
Nintendo
Just hurry up and show smash bros so hyped by this stupid game and Sakurai van go make another non smash game.
Beyond that
Bravely default
Dragon quest X
Retro,s new game
Monolith Wii U RPG
3DS Zelda
3D Mario
GBA VC
Wii U VC
Disney announced they are buying Nintendo
Google/apple
At Google I/o were going to see a minor step at them showcasing gaming features in key lime pie. Ingress goes out of beta.
Apple won't do anything.
Both continue to push Nintendo and sony handhelds into the basket we see symbian phones and blackberries.