First of all, if you don't already own the other three books so far in the Archive Series (Story, Animation, and Design), WHAT ARE YOU WAITING FOR??? This is by far the best art book series Disney has released yet, and it demonstrates a commitment to displaying the true (often unsung) artistry of the Disney animated films, without the excessive self-congratulatory commentary of many of the recent Pixar art books.
While the other books in the series have beautiful art as well, what makes Layout and Background a real gem is how much of the work collected here really is never-before-seen. If you own a few other Disney art books, odds are you've seen concepts from The Lion King, or animation drawings from Beauty and the Beast, but you've probably never seen background art from the Pluto short films. In fact, the layouts from the many short films (Mickey, Goofy, Silly Symphonies, the Disneyland TV show segments) are the big surprise of this book: the level of craftsmanship is shocking, easily just as impressive as in any of the feature films, and often spanning a greater range of styles.
The only small complaint I have about this book is that, compared to the 2D films, the editors really seem to have phoned it in on the background samples from the 3D films: instead of showing the layout art that went into creating the detailed 3D environments, they just show final renders, and not even the best ones, at that. There's a full-page image from Bolt that I almost wanted to rip out of the book (and I liked that movie!). So, note: if you're looking for background art from the 3D films, you're going to need to pick up the art book for each respective movie. Otherwise, this is a magnificent addition to any artist's collection, and a great coffee-table book for the everyday Disney fan!