me personally....i think hl2 and d3 are the key games. (unfortunately they are not out) but...because of their engines they will probally be used many times over in other games. look at quake 3, STILL being used today. i doubt we see a game based on the crytek engine anytime soon
opengl not a teller about cards performance? err ....wha? d3 anyone?
like Arioch said ...both cards will probally run great on both hl2 and d3. (unlike theif3 and far cry). and that WILL be a big factor for the future.
but lets not start a flame war or nothing about it