As far as I can remember, all the menus are changed, with a lot more options, some of them new and others you previously had to access via "pre-game-launcher", such as fps-limiter, load textures on demand, etc.
It should also optimise the game a lot more for decent rigs, and then there are new features like walking (holding "Control") and more keybinds in the menu.
The only problem is it only works with DX9 (so you need a decent rig).