Photorealism? Sounds like enter the Matrix to me. Soon enough we would not be able to tell the difference between Video Games and real life.
at least graphically (and audio-wise)...
...but, no matter how photorealistic, there always will be some other differences left between games and real life. for example:
say you lose a battle/mission in a game. you probably will get taken over to some continue or menu screen where you can start said failed battle/mission over again. so at least you get a second chance in the game.
but in real life there are no second chances whatsoever and there never will be. here, any damage you suffer cannot be undone, and time cannot rewind for you to reverse any harm done to you. there's no turning back, and believing in second chances in the real world is just wishful thinking. once you lose a chance at victory, it's lost forever, and you'll have to live with it for the rest of your life.
and also, don't forget that there probably will still be some cartoonish game figures left even when the time comes for photorealistic-looking games.