GRAW was very mixed in terms of quality in my opinion. Therefore I left it from the list. Some parts are very impressive while others are.. well less impressive...
Crysis is probably going to be the best looking game when its released, however I haven't played it so I left that one out too.
S.T.A.L.K.E.R could still turn up good but I doubt it will have killer graphics.
As for Prey, go get the demo. Its a nice little preview of it...
