Theres an important feature coming up for HTML5 browsers: Mouse Lock.
It's still in beta status but you can activate it in the Chrome Browser under chrome://flags/.
Without Mouse Lock you can't really design an Ego-Shooter neither any First Person Game.
A Sample Implementation of Mouse Lock with jQuery:
> Pointer Lock Example <
Only Working in Chrome!
Theres an successful Port of a Quake 3 Map with WebGL and Mouse Lock. http://media.tojicode.com/q3bsp/
