Story: Isn't some bullshit get this legendary crap and save the world through out the whole damn series. So it's unique compared to other stupid fantasie books.
Action: The action parts of the book were written so well you don't even have to try to visualize it, you just see it. As for in the movie, fuckin epic.
Characters: They change as they grew up like actual people, and not some bullshit, I'm the chosen one mature crap lots of other books give you.
Overall the book was well written, if anyone other then Rowling tried to tell the story of potter it would be utter bullcrap like all the other fantasie books