This post made me realize how long it's been since I've read a well paced book. I think the genre determines pacing a lot of times. YA/Children for example have a tendency to be faster paced to keep the attention of their readers. Slow burns are more common in Fantasy/Sci Fi, and you'll get some slower paced books in really angsty romances sometimes too.

Out of curiosity, what genre do you read in?