I never though I'd say it, but there. You wont miss anything.
It's not that the book is bad. Writing is serviceable, and plot is interesting and moves. But it's the kind of story that is better served by a speedy delivery. It lacked most of the punch of the movie.
One of the aspects that flagged more egregiously in the book was Norman. Here we have this supposedly crack psychologist, and he is dumb blind to everyone around him. Makes you want to shake him. And its much to do with a time factor: I don't remember having enough time to think about that one while watching the film.