The developers at Blizzard came up with a little present from our friends at Nvidia: Three-Dimensional Massively Multiplayer. Not just Direct-3D or OpenGL, mind you: Three-Dimensions. How? Through some awesome, yet stylish glasses. Not recommended for night-driving or hang-over headache prevention. C-Net even got excited, and wrote up the technology. Fascinating stuff, and I'm sure none of us can wait until this is mainstream!

Source: 3.0.8 Patch Notes