Picking up this book, the first thing I noticed was the overall quality of it as a physical object. The design - cover, font, layout - as well as the materials used (cloth for the cover, and heavy paper stock for the inside) are just great. The reproductions are rather small, as many have noted - larger reproductions might have meant a less classy looking design, but would have been more pleasurable to actually look at. However, this book is for people already familiar with Leibovitz's work, who presumably don't need to see the larger images of her work.
Leibovitz writes in a simple, direct, candid and concise way. It's like having a great conversation with her about a wide range of topics concerning her work and photography in general. The great thing about Leibovitz is that you never get the sense she's augmenting or exaggerating things to make herself sound better. If anything, she's modest about her methods and achievements.
Is it a perfect book? No. One often wishes she had expanded a little more, delved into the well of her memory a little deeper. She's had so many opportunities to photograph such an extraordinary range of people. This book seems like a distillation of the essential stories and ideas she wanted to express. There's enough here to satisfy, but 'just enough.' Perhaps that's for the best, since it leaves one wanting more.