My guess (as well as my hope) is that games will be taken further in the direction of immersion. In the last decade of gaming, we've had an upsurge in games which make you feel like you're part of something bigger than yourself. We've crept through the halls of a once-splendid underwater city, still haunted by the ghosts of its past. We've read graffitied messages on safe-room walls, some serious, some facetious. We've found our way through crumbling apartment complexes, littered with the bodies of their former occupants.
Immersion is what I value in my games most of all. Take Bioshock, for example, which is probably my favorite game. As much as I love the gameplay, including the excellent combat system, it is the immersion that makes this game so exceptional. It is lucky the gameplay is so elegant, or else it may have gotten in the way of the oppressive atmosphere, which filled me with incredible paranoia throughout.
To further immersion, graphics will continue to improve. Many games have already crossed the uncanny valley to become pleasing again, and soon, all commercial games will have reached this point. It is possible that the industry will experiment with 3D at some point in the future, considering the role another dimension could play in immersion, but what sort of technology and when are far beyond my reckoning. I just hope it's not one of the 3D technologies they're using in movies; I'm not a fan of the 3D craze.