It's possible I'm just too nostalgic about the movie to judge the book fairly, especially reading it for the first time when I'm almost 40. But I really don't think the book works as a cohesive whole. There are basically two completely different stories with no real connection between them -- the adventure story I knew from the movie, followed by an inexplicably darker, rambling, dream-sequency second half during which Bastian (spoiler alert) decides to usurp the empress and literally has thousands of Fantasticans slaughtered on his journey to discover that he'd rather be a normal kid on Earth than a fascist dictator in Fantastica. He actually slices open Atreyu's chest with a sword at one point. It's very disturbing.
That said, my 9-year-old -- who hasn't seen the movie -- loved the book, and he's the target audience, I guess. And the overall message is positive, if a little vague. And I'll always have the movie, with its uncomplicated triumphant ending where
Sebastian fixes
Fantasia forever and everyone's happy and he and Falkor chase those stupid bullies into a dumpster. Really, how could I have expected Michael Ende to have topped that?