Why have vampires become so popular in books in recent times?

Vampires have always been popular, there's just been a lot of publicity to recent books. Good heavens there's been many ventures in books, tv and movies about vampires: Dracula the book written in 1897, Nosferatu the film from 1922, Bela Lugosi as Dracula in multiple films in the 30's and 40s, fun Abbott and Costello movies in the 1950s - Dracula, the wolfman and frankenstein in one movie. In the 1960's there was a very popular tv show Dark Shadows, Anne Rice's novels about the vampire Lestat starting in 1973 and the film Interview with a Vampire starring Tom Cruise and Brad Pitt (wildly popular), the exquisitely beautiful and very romantic film Dracula starring Frank Langella in 1979, the film The Lost Boys 1987, Eddie Murphy in Vampire in Brooklyn in 1995 and Wesley Snipes as Blade in 1998, Charlaine Harris' book series about Sookie Stackhouse and her vampire Bill starting in 2000, It's not sudden, and no recent boom in popularity as it has always been a popular subject - it's just you guys have now discovered it, there was extra promotion for the movies and the additional popularity caused by the wildfire spread through the internet.