I think I might have to give a dissenting opinion here, and say that it might be a bit awkward for me. I'm a hetero male, and I don't think I'm a homophope or anything, but....
I think I'd have some reservations to having a roommate who was gay. The way I see it, the situation shares some characteristics with having a roommate who was a heterosexual female. Not that I'm fundamentally against either idea, I'm just saying there's room for awkardness in both scenarios, awkwardness that I don't think would happen with a roommate who was another hetero male.
Let's take the idea of, i don't know, changing clothes. I wouldn't find a problem with it with another heterosexual male in the room. However, I would feel a little awkward with a hetero girl in the room. I would just be... shy, or reserved or whatever. I think that same feeling applies if it were a homosexual male.
... does this make me a homophobe?