Im personally looking foward to Resistance 2, Motorstorm 2 and Silent Hill 5 as far as exclusives go. (I think silent hill is exclusive). Killzone 2 looks very good as well.
Im also intrested in Alone in the Dark as the PS3 version is being enhanced and getting more content.
For me at the moment though Warhawk is by far PS3s best exclusive. Me and the girlfriend have clocked over 300 hours and never get bored with it. The intensity of the battles, the freedom of how to fight, the huge maps and the random things that can happen make it a really fun experience. Great social game to with the four player split screen.
I must also admit I like a bit of Resistance FOM MP. I mean its not the best FPS ever made but the MP battles can get very intense and brutal.
Get Wahawk Mr Pico and we shell make war together!!!

Well.... a bit anyway, im still playing GTA4 ALOT at the mo!
(On a side note: Im very very happy Bioshock is coming out on PS3! With extra content YAY!!!)