Vampires have been popular for quite some time, someone who is immortal, powerful, and sexy (both male and female), is always attractive, but to "balance" that out in popular culture they had to drink human blood, and commit a rather serious crime, cannibalism. Lately that idea of the classic vampire is very attractive, in a dark sort of way. Dracula being a prime example.
Now, we have things like Twilight, they make vampires out to be day walking sissies who care if a human cares about them, to me it makes me sad for the whole vampire mythos, it kind of takes the whole power and uncaring immortal thing out of the equation, which IMO made vampires interesting. I am glad there are a very few things out there making vampires look awesome, like the show "True Blood".
I agree though, the insanely popular (although I don't understand why) Twilight, makes vampires out to be complete sissies.