I'm not sure what my sexuality is. At times I think I'm heterosexual, other times bisexual, and then sometimes asexual; I'm just... sexually confused. I feel that my bisexuality/attraction to men is whenever I'm single, and I probably would end up with a guy if he were incredibly sexy/hot to me. I also find myself lean more towards women, because for every ten women that I'm attracted to, there is only one man that arouses me. And on the porno topic: I could never watch gay porn... or even lesbian porn--I need M/F.
But on subject: I could see why the study considers bisexuality a myth, because people do end up choosing one gender or the other. I still wouldn't say that's an accurate observation, since a person that claims to be bisexual would choose a person based on who they got emotionally involved with first, rather than their gender alone. I guess bisexuality could also be considered a sexuality that comes in phases, like those above me stated: sometimes you're attracted to women more at one point, and men another.
What I do know, though, is if I were a woman, I'd love to be bisexual so I could have a boyfriend AND girlfriend. ;p