Anyone wishing for GTAV needs to be realistic, there's close to 0% chance of it being exclusive, timed or otherwise, to any platform.
Anyways, mine is gonna be what I expect, from most to least likely, not counting any PSP/PSP2/PSN announcements since OP just wants PS3:
1. Move games - just like Natal, this is certain to be there, I hope HSG and HST make an appearance or maybe Civ Rev 2 or Civ 5
2. 3D Games - just as certain as move games, montage of 3D games like GT5 and SSHD, should also have some playable, hope it's good
3. SOCOM 4 blowout - Hope for online offline co op campaign and extra co op missions. Only thing missing right now from it.
4. Gran Turismo 5 blowout with Release Date this Fall
5. inFamous 2 - website is already registered + twitter of the voice of Cole, should be there
6. Resistance 3 - poster in movie leaked, has a good chance of being there and out this year
7. The Last Guardian - don't know how much they'll show but should show us some more and give a release window
8. God of War 3 DLC - we know it's coming, we should find out what that is at E3, maybe before though
9. Play Create Share next game - probably won't talk about it much as they'll still be pimping MNR, but I expect MM to be responsible for this, LBP 2 seems likely, but would like to seem them expand Kung Fu Rag doll and make a real PCS fighting game.
10. Demon's Souls 2 - Best game of the generation deserves a sequel
Bonus wishlist for PS3 only:
1. GTA V - Don't expect it until after Agent
2. FFXIII International - With all the content that was cut, maps, ships, ability to go to all differrent towns, etc
3. KH3 - multiplat or otherwise, I'd like to see this
4. Monster Hunter - still haven't bought MH3 yet but the PS3 is the only system without MH, so would like to see Capcom throw a bone here
5. Dragon Quest - don't even wish for X because I'll have to play that on my Wii, but a spin off of some kind would be nice, maybe even DQ4 and DQ7 on PSN, that would be nice
6. Trophy patch for older games, never gonna happen, but would be nice to get a trophy patch for some games I have like MGS4 and HSG5 and Ratchet FTOD
7. Syphon Filter next - please, this needs to happen, I hoped and hoped for SOCOM 4 and it happened
8. Twisted Metal - I know Jaffe said his next game is not this and won't be at E3 but I hope he's lying
9. Sly 4 - Hope after inFamous 2
10. Naughty Dog's next game - I expect ND to announce U2 GOTY and show a teaser of their next game, I hope it's Jak and Daxter
11. More up ports collections - a shot in the dark but we all want that, ICO/SOTC has a chance of seeing this prior to TLG release.
12. The Getaway and Eight Days - those games had potential, please revive them
Gonna stop wishing here or I'll go on for awhile lol