I like happy endings in a book. I want the hero to come out on top and the bad guy to find justice. (or Karma...that's sometimes as good as justice) I also want closure in a book. Tie up the loose ends and finish all parts of the story. I try to do this in my stories and I hope my readers think so.
I also like to leave them looking for the next book. Just a little whisper in the last page that lets them know part of the story lives on. Not in the way a serial would do it, but more like one or two of the characters coming together to form the a totally separate story.
Sometimes I wonder if I'm torturing the reader by doing this, but maybe its just the writer wondering...what if?
In Betrayed by an Angel, one of the angels is reminded by the higher ups that his work isn't quite finished and the last page is that scene. The the book ends. I've started that next story but haven't finished it. Will my readers get mad if I'm slow to the gate with that next book? I'm not sure. I haven't really given enough information to explain the next book, but just a little tease.
Do you make sure all story lines within your story are closed? Do you always have a happy ending? Or do you end with a teaser?