I haven't seen a massive amount of the E3 coverage so this might change but at the moment
Definitely
No Man's Sky - The more I see of this, the more I want it. I can understand how people see something that could ultimately be a slog but exploration in games is my favourite thing. If they can nail the rewards for finding stuff then this could be incredible.
Firewatch - Been following this since it was initially revealed.
Horizon: Zero Dawn - Looks like Monster Hunter with robot dinosaurs so count me in.
Star Wars: Battlefront - It had me just with the sounds in that bit from the Sony conference. Those Tie Fighters just sounded
My 9 year old self was just entranced.
The Last Guardian - Could be incredible, could be terrible. I'm willing to take the gamble.
Shenmue 3 - I really didn't like Shenmue 2 and so that is why I've signed up for the Kickstarter - sometimes I just get swept along by the hype.
Probably
Uncharted 4 - Maybe not at launch but definitely at some point.
Fallout 4 - It's inevitable I'll pick this up even though I just don't have time for massive RPGs. That's why I'm currently playing Witcher 3 in 30 minute sessions (thank god for the PS4 resume mode), I'll probably have finished it just about when Fallout gets released.
Maybe
Morpheus - If it isn't stupid amounts of money then I might take a punt. This is the reason I've got drawers full of shitty peripherals that I never use (PS3 keypad, Move controllers, PS4 camera), I shouldn't be trusted with money.