Don't think Sony has anything. They'll talk about Project Morpheus which is their VR headset and they apparently have some 1st party studios dedicated to making content for it.
We'll probably see some more of Uncharted 4 and No Man's Sky but I'm not sure they'll have a real big wow up their sleeve.
Uncharted 4 is going to be there for sure as is Morpheus (just hope it's brief, only so much you can show of a VR headset). No Man's Sky still looks like a game that'll get boring after 2 hours based on what they've shown so far, hope if they show it, they're able to persuade me otherwise.
Ratchet and Clank has been shown off already so it'll be pretty boring if they show it off for long.
They'll probably have a longer trailer for Persona 5 (massively looking forward to that one).
Last Guardian would probably be a show stealer if they actually showed it. Given people have been waiting years for it and we've seen almost nothing, still seems unlikely.
Square Enix could show off some of their games at Sony's show or save it for their own (FFXV is certain, Kingdom Hearts 3 is likely, FFVII remake is heavily rumoured).
Outside of that, not a clue what they could be showing. I do know that the Vita will be lucky to be on screen for more than a couple of minutes, if at all.