Here's what I think we can realistically expect from Sony studios:
Polyphony: I think we may get a reveal of their next game
but I don't think it will be ready to release before late 2016.
Me: No Tourist Trophy 2/GT game will be revealed. So I expected nothing from them during the E3 presser. No show
Sucker Punch: Nothing on their next game. It's only been about 16 months since Second Son. They probably won't have anything ready before early 2017.
Me: Too early. Nothing to show yet. No show
Naughty Dog: Obviously UC4 will be there probably as Sony's main game, but I also think they'll reveal Uncharted Collection for release this November.
Me: Of course UC4 will be shown. Maybe a Uncharted collection, but not from Naughty Dog.
Media Molecule: Tearaway Unfolded will be there, and I don't think they'll reveal their next game until after that has been released - probably PSX this year.
Me: Media Molecule's new game/IP will be there for sure.
Evolution: I doubt they'll be there at all, but if they are it will probably be to pledge continued support for Driveclub and maybe to give a date for the PS+ Edition.
Me: Nothing from them. My guess is this studio will be closed after a year.
XDEV: Hopefully they'll have a presence there, with Alienation, Shadow of the Beast, Rime, etc.
Me: They devs of these games will be there, yes.
Japan Studio: Hopefully Gravity Rush 2 and another game. Hoping for but not expecting You Know What.
Me: Very likely that one of theirs games will be there. My guess is TLG.
Bend Studio: Looking forward to seeing their horror IP. A release this year is probably a little too soon (it's
just over 2 years since Golden Abyss - I'm an idiot as it's been more than 3 years), but they might be ready for a reveal.
Me: Very likely. There now IP will be there imho.
London Studio: Hopefully more Morpheus stuff, and some full games rather than just demos.
Me: Morpheus stuff will be there.
Santa Monica Studio: I expect nothing, besides Everybody's Gone to the Rapture (if we count it as 'theirs'). I think we'll get a GoW reveal at PSX at the very soonest, but I'm expecting an early 2017 release so hopefully E3 next year.
Me: Nothing from SSM. GOW4 will be at this years PS Experience, imo.
San Diego Studio: I don't really know much about these guys - the MLB studio, right? I guess Kill Strain and Drawn to Death might be there.
Me: Drawn to Death and Kill Strain will be there.
Foster City Studio: Don't think they'll be ready to show anything yet.
Me: Foster Studio doesn't develop its own games. It's a "support " studio.
Guerrilla Games: I hope Horizon will be Sony's centrepiece reveal. It
must be at a point of readiness by now.
Me: Their new IP will be there.
Guerrilla Cambridge: I think they're developing the next mainline KZ game, but they're relatively small and I don't think they'll be ready to show it this year.
Me: Too early. Nothing to show yet. No show
PixelOpus: Probably nothing yet. They only released Entwined aat E3 last year, so probably not ready for another release or reveal before this time next year.
Me: Too early. Nothing to show yet. No show
Partner Studios: I don't think Quantic Dream will be there, as I don't think they'll be ready to release before late 2016. Ratchet & Clank will hopefully be there in force and I'm interested to see the new game from Level-5. I'm hoping for more Dark Cloud, but not holding my breath.