Laura Miller has an instructive piece on Salon that I wish she'd published back when I was in grad school. I remember lots of discussions at Emerson about the craft of writing, but I recall very few conversations about what readers want from a piece of fiction. Miller's essay, "A Reader's Advice to Writers," is full of good counsel if you aspire to write novels or short stories. You should read the whole thing, but her five bullet points are useful tips in and of themselves:
1. Make your main character want something.
2. Make your main character do something.
3. The components of a novel that readers care about most are, in order: story, characters, theme, atmosphere/setting.
4. Remember that nobody agrees on what a beautiful prose style is and most readers either can't recognize "good writing" or don't value it that much.
5. A sense of humor couldn't hurt.
Worth pinning over the writing desk.