I recently played Half Life 2: Episode 1 with the commentary on. It's very interesting, actually, and gives you some nice Game Design information.
I was wondering, if I (or anyone else) put an Audio Commentary system in a game (as an extra option, or after you beat the game), would you play through the game again to listen to it?
I probably would, if I liked the game. I think it'd be nice to hear the developer's thoughts on the general design and little points of interest, or perhaps an area that was particularly difficult to create.
I've always felt commentary from quality media has always been a great inspiration for making decent media myself. I just choose not to release any of what I make.
I remember Rebel Strike (Gamecube) had an audio commentary for each level in the game. I never bothered sitting through any of them though. It was difficult enough to complete a level without having two geeks talk about the game engine in the background. Ecks-dee.