I just learned that there's a such thing as an asexual person when reading the biography of Janeane Gorafolo (http://splitsider.com/2012/02/saturday-nights-children-janeane-garofalo-1994-1995). They have a need for emotional companionship from the opposite sex like everyone else, but they apparently don't have a need for physical intimacy and this group makes up 1% of the population. They even have a support network online.
Now consider how various ethnic and sexual minorities have pressed for change in terms of seeing more of their kind on TV and how with enough pressure, TV shows have cast more gay, black, and Latino characters. I've read about black people recalling how seeing Uhura on Star Trek or the Cosby Show had a powerful positive effect on them. The flipside of that is what if you're asexual and don't have much interest in sex, it must make you feel very alone to be surrounded by images of people who's end goals are driven by relationships and sexual. A disproportionate number of TV character arcs are written that way because it makes for more compelling drama. Media studies classes (or at least, my media studies class) note that discrepancy between the end-point of stories always being love and real life. However, TV conventions still haven't changed too much.
Considering most TV shows
(especially) gear their characters towards an endpoint of falling in
love with someone or having a relationship, it would have been nice to
have a character on TV who is asexual.
Sheldon on the Big Bang theory is a refreshing change to that, but they paired
him up with Amy. I love this show but I've really only seen the
first couple seasons on reruns, so I'm not the expert, but I wonder if
his relationship with Amy is representative of an asexual relationship.
If it isn't I'm pretty disappointed. It's probably fans saying "Sheldon
should be happy and find love" and I don't think it was necessarily
organic to the character, especially considering there are actually
people like him.
[Update: I have yet to see a 4th season episode, but I understand from message board reactions that Amy and Sheldon's relationship is indeed asexual. So good for the Big Bang Theory for putting minorities on TV in more ways than one!]