We've come to the point where graphical fidelity is good enough. Some people are dismissive of the concept of diminished returns but I see we are already there. The only way to truly compare these graphics is with actual screenshots at the right resolution, FPS comparisons, actual numbers thrown in the mix, in summary, things only the really enthusiasts care about (and are able to differentiate).
There's stuff like number of enemies, view distance, but those are far more specific to the game itself, it would be dumb to judge, say, Silent Hill on how much draw distance it has, or any other claustrophobic game.
Maybe some disagree, but it has become irrelevant to me at this point, I'm really liking what I see in the WW screenshots, and I know that has to be doable in the HD twins. Art direction is whats really going to matter in this gen.