We honestly don't know which looks better, because PS3 GAMES tend to look like shit over the internet (example U2, AND KZ2) especially good looking games..
From what I have seen over the net, ALAN WAKE is well ahead of U2 graphicly on the NET. But on screen U2 looks like a god..
seriously its really hard to tell without having both games in hand, I remember when people said GEARS 2 had better graphics than U1 based on internet video and screens, and we know that U1 is almost a mile ahead of it visually.