Forum Overview :: Gamerasutra :: Wasn't it just a button toggle originally? Like in Duke Nukem.

[quote name="Worm"]Mouse look in those games makes everything look like shit and is pretty unnecessary because of auto aim, then you end up scrambling to find your original level of view so things don't look crooked. I preferred just using the toggle, though I'm amazed this the first time System Shock 1 got the ZDOOM treatment.[/quote]