Time or Place. Do you have strong preferences/dislikes either way?
I tend to avoid books set in Australia and Maine. I think I read too many Stephen King books at once and I got tired of reading about the place.
I don't generally enjoy reading books set in my city either and if I read Sci-Fi then I prefer it to be set on earth.
Another pet peeve is books that are set during the past and the present. I'd rather the whole thing be set in the past than jump back and forth.
What are your preferences?