Being bi, I guess I'll have to answer the question about dating straight/gay people. Hm. By what's largely been random co-incidence, I've never gone out with someone who hadn't at least had thoughts about both sexes. (Then again, it's not as if I'm anything like past the 'experimenting' stage of life). Coming from that, I think it'd feel sorta strange to date someone who's fully straight or gay. I just find it weird that someone can find X hot, but not Y because he/she is a boy/girl. But once I get over that (and I'm sure I will soon enough), I don't see anything particularly standing in the way.
Thinking about it, it's sort of less competition, too. An advantage, I suppose. Hm. Though that is one of the most shallow reasons to go out with someone that I've heard. :\
J-N-K