I love true stories.
I think it's because I'm constantly amazed, intrigued, inspired (and sometimes appalled) by genuine human behavior. Inventing characters is a lot of fun but I don't think I'm capable of creating a fictional character that could possibly be as dimensional, idiosyncratic or fully realized as the actual people I read about in the newspaper every day — which is another way of saying that when you're telling a true story, life itself has done most of the work for you. That makes things easier.
I also like the feeling I get when I'm working on a true story — a sense of authenticity, that I'm really reporting and not just writing.