I gravitate to erotica & especially erotic romance with all the different sub-genres that fall under it. I find that if there is a romantic relationship throughout the story, that it's more interesting for me, (and course, the more explicit the sex, the better).
Fantasy is my first choice. I don't really get into young adult novels or the whole vampire genre craze that's going on but hand me a mercedes lackey novel and I'll sit for hours reading. Some mystery are okay but most of them make for boring reads.