I can't wait for The Last Guardian, but in all fairness that won't come out until 2010.
I'm enough of a fanboi (well, fangrrrl I guess) of the Katamari franchise to be psyched for Katamari Forever, although having played the demo I'm feeling a little cranky at their continued abuse of interaction design.
Can't wait for Brutal Legend!
Really really can't wait for Ratchet and Clank: A Crack in Time!
Intrigued by Heavy Rain but not sure if it will actually be any good.