when it came to kz2, uncharted2, heavy rain and gow3- all the great screen shots aside, I chose to wait until I actually played the games and seen the graphics for myself. This was a logical way of knowing that the game is as good as the screenshots and the game does what it has been said it will do.
I'm not saying Alan Wake looks bad or great. I'm saying it has the potential to live up to everything which is being said about it, but whether it does that or not, we will only know when we actually play the game.
To give you a great example, GOW3 trailer was shown yesterday and pretty much everyone who seen it went nuts, but until I know that is actual in game gameplay graphics I am not going to say it will rule above all else forever and beat every 360 game etc. Although for GOW3 there is some proof since I have played the demo and everything from draw distance, lighting and textures looked phenomenal.