Based on Charlaine Harris' series of southern vampire mysteries, the show somewhat follows the plot line of the books but veers further and futher from it as the series continues.
The series does deal with racism, interracial relationships, sexism, classism and homophobia. One of my favorite characters is Lafayette, an openly gay chef. The vampires-as-gays metaphor that one finds in so many movies and books also permeates this series (a hidden and much hated community that is really more complicated than most people imagine).
However, if you don't like shows that are really scary, don't watch this one.