There is a pretty good documentary on MMO players by the name of Second Skin that may be just what you're looking for. The people it chronicles are, quite frankly, not the most well adjusted gamers. The documentary, however, does a good job of not demonizing the games but instead looking at the minds of the players who allow themself to be drawn into them to the degree that it can negatively impact their lives.
Edit: You can actually watch it online at http://documentarystorm.com/second-skin/