hi homeboy..sorry to hear about your situation.. but i can totally relate.
my boyfriend was a world of warcraft 'addict' for about 2 years. my experience is that you can't force someone out of this situation..it is a decision they have to make for themselves.
although, i had to break up with him for a good six months. he numbed himself with the game, speaking only to his online friends through a microphone as well. eventually he realized that he had no 'real life' and was wasting his life away as a blue troll. -__-
this was the video that inspired him to quit (it's geared towards wow addicts, so not sure if it'll work for your roommate though):
Good bye blue sky - Google Video
it wasn't that groundbreaking to me, but i think he was on the verge of quitting anyway.
anyways, it's nice of you to worry about him, but part of me thinks you're just disgusted that he's living his life in a way that you don't agree with. i had the same problem with my roommate, but then i chose to accept her for who she was.. i just chose not to be around her as much. now she doesn't drive me crazy anymore and we have very cordial relations.
it's probably really annoying to look at him wasting his life, but don't let that waste YOUR life. he'll snap out of it when he's realizes what he's doing, but until then you can't physically force him to not play.
"a man convinced against his will is of the same opinion still."
and plus, you're going to be graduating so soon..once you move out, i doubt you'll even think of him anymore.
sorry this is so crappily wrote, but im tired. good luck!!