I said in another thread (cant remember which :p) graphics do come into account but i would rather a game had a good stroyline and game play rather than graphics.
For example, Grandia 2's graphics literally hurt to look at when I first played it but, I still found the game enjoyable and is now one of my favourites.
I agree with ShadowV7 and DCK. I would never buy a game just because it had good graphics.