I have to say I'm also one of the undecided. I tend to read whatever looked good at the time. I go through phases of reading non-fiction for several months, then fantasy or sci-fi, then mystery. I always wind up with a Terry Pratchett book around my birthday, so I guess there is some pattern to it. I have to admit, I have never read a romance novel.
I do get easily bored with the "adventure fantasy", there are only so many times you can read about a hero and his elf/dwarf/dragon/orc friends without feeling like you can guess the story line.
And I have my fall backs too; Charles DeLint, Stephen King, Agatha Christie, Terry Prachett, and Tim O'Brien.
