Full disclosure: I have a vampire novel for adults (Blood Groove, Tor 2009) coming out next spring, so I’ve put a lot of thought into these ideas. I agree completely, and more, I think when you lose the idea that becoming a vampire means giving up some very human traits (aging, death, sex in some cases) you also lose the power of the metaphor. A character can certainly fall in love with, and therefore want to become, a vampire, but shouldn’t it be an ambiguous ending at best? If it’s not, if they live happily (for)ever after, then what’s the point of even using the vampire as a concept?