That last post draw a bunch of comments, mostly thanks to Michael J.W. Stickings’ link from Crooks and Liars (thanks!). A few favorites:

Alek Felstiner posted on Facebook:

This is why Tim Bayliss was such an uncomfortable character for everyone else on Homicide. I think, related to your point about lesbianism not being “sex,” there’s a sense in which male homosexuality is contaminant (except perhaps, notably, in prison, where the concept of masculinity is by necessity revised, and that revision recognized and tolerated on the outside), whereas female homosexuality is tangential and easily disregarded – if not encouraged and fantasized-over.

I make that point because most narratives, especially on TV, are about redemption. Ending up in a heteronormative relationship is a satisfactory conclusion for a mainstream American audience, but it only really works if it’s a woman (who finally finds the right man). A bisexual man eventually finding the right woman doesn’t offer the same narrative closure, because he’s already been “contaminated.

Nulwee at DailyKos wrote:

Bisexual men [on TV] in my experience are usually sexual predators, like Skins antagonist/anti-hero Tony.

Kalafudra wrote here:

I think a part of this problem is also that the context we usually see Lesbian sex in is as a turn-on for straight men and not as sex in its own right

And lots and lots of people mentioned Torchwood.