True 3D is the next jump in video gaming. Current systems render a 3D image on a 2D surface, basically a 3D world behind a window. Because the human brain see's depth using stereo vision, you can reproduce the effect using stereoscopic technology. I used to mess around with this back in 2001, but back then the computational HW didn't exist to make it viable. Playing on a good CRT monitor at 85/42.5 hz at 800x600 (1024x768 high settings pushed the GPU too hard) gave a surreal experience, especially in Unreal Tournament and AVP2.
Nowadays we finally have the GPU horsepower required to fully render two separate in-sync frames at high resolutions at the same time. And we finally have the display tech capable of displaying those two frames on top of each other on the same screen. Also game companies are now aware to make their games naively compatible with stereoscopic displays. The GFX driver doesn't have to do hand-waving magic to render two screens. This makes for more consistent game-play and less graphics glitch's. Personally I'm waiting for a 150hz capable screen so I can do 75hz 3D displays. 120/60 produces very little eyestrain but it can become a problem if your happen to have a florescent light overhead (they pulse at 60hz).
After 3D displays they need to get virtual interfaces working, hand / body motion detection and possibly holographic displays .... my dream.