For me, it's Red Dead, 'cause of the promise of a free-roaming western title. The story looks to be a really compelling one too (at least as far as Western vigilante stories go)
It would have been Prince of Persia but... I kinda liked the different style the series was taking with the most recent title, but now they're just going back to the Sands of Time trilogy, pretty obviously to cash in on the movie. It's just such a misguided series in my mind, like it has no idea the kind of game it wants to settle on being.
imo, Alan Wake looks interesting, and I was interested in it 5 years ago when it was announced, but these days, I'm wary of something that takes nigh on a decade to finish, and I never pay full price for a title from an untested series.