The 360 doesn't support DX-10, does it? So what was the whole big deal about the "Alan Wake is being developed around DX-10 and will be DX-10 exclusive" announcement a year or so ago, then?
As for the gameplay video from E3, it looked pretty damn underwhelming. Walking around a dark town and setting people on fire with your flashlight? Didn't exactly thrill me to death.
It also seemed to run slower than dirt. The one zombie who attacked with a shovel or an axe, or something, iniated his attack and it took 3 seconds to actually land on the player.
So if this is 360 only, eh, I doubt it's much of a loss.