(Before I get to the book, did anyone watch the Brave-themed episode of Cupcake Wars last night? One of the contestants had to make a mutton cupcake.)
I have two complaints about The Art of Brave. One, not enough Mike Mignola concept art - - his contributions are limited to architecture. And two, I'd inferred a certain aspect of the plot that hasn't been revealed in the trailers (I think it was the toy set that gave it away). Some of the concept art emphasizes that secret, so you might want to avoid the book until you've seen the movie.
Otherwise, it's a gorgeous book, full of sketches and paintings by Steve Pilcher and Noah Klocek, sculptures by Greg Dykstra and Andrea Blasich, and lots of storyboards.
The Art of Brave is 42% off at Amazon and filled with art you'll want to stare it.