Most important thing in choosing a book to read

When you are choosing a book to read, what's the most important thing you look at? The cover, the summary, the author, the title, reviews, or something else?

Although I use a combination of the above (like most people, probably), I would have to say reviews are the most important. I like to see what other people like or dislike about the novel. The one I could probably care least about is the author. If I like one book by an author, I try to read the others, but if I dislike a book by an author, I try to give his/her other books a chance. I also love discovering new authors.