Yes, Flight Simulator X and Far Cry 2 do indeed look amazing. DX10, or whatever the oficial name is, IS going to be amazing, no doubt.
And stop fretting, you don't need a DX10 card to have Vista or any of Vista's games. That would be stupid...BUT, you won't be able to get DX10 performance from DX9 cards. With a DX9 card, you'll be running at DX9 graphics.