Also, aside from the obvious example of WebGL, what's something important that IE10 doesn't do?
* Device orientation
* Full screen
* Mouse lock
* Web Audio
Mouse lock doesn't matter without WebGL IMO, especially since some browser vendors require Fullscreen first.
Web Audio and Device Orientation are quite important, though.
Also, aside from the obvious example of WebGL, what's something important that IE10 doesn't do?