Writer's Fallout Shelter

Haha, ok, let me try to take a crack at it. Um...

Anne Rice made them sexy, which is interesting because her vampires, once turned, are sexless. Buffy made them popular, Angel continued that, and then the age-old "Who would win in a fight" question came about with Underworld and Underworld: Revolutions. Then there was a slight turning toward werewolves with the whole Blood and Chocolate bit, and then the Twilight series came out with the continuing of the Vampire/Werewolf sensationalism.

Vampires are said to have a bite that is so erotic that it is an orgasm when felt. They may be sucking on your blood at the time, but that's definitely not what your body is telling you. There could be some magical realism explanation for that, some sort of enzyme secreted by the glands from either within or without the teeth that gives off some sort of Novicane and/or euphoria... or something. Then, of course, there's the REALLY old version of vampires where they bite you three times, the bite is still glorious, but after the first bite you fall more under their hypnotic control.

Basically, currently, it's a fad of hollywood where they're taking a bit of fantasy and running with it, one that's so incredibly fantasy that it hasn't been touched in a while and so the public would, so to speak, drink it up. You might as well also ask, "Why Zombies" because of all those zombie movies that came out for a while there. Or, "What is it about asteroids or the earth shutting down?" They're fads. Plain and simple.

Hope that helped...