This is the first book I've read on WPF, and I think it got me off to a good start. I got a solid understanding of the underpinnings of WPF by reading the first several chapters. I started reading this book sequentially, but finally skipped a couple chapters on graphics. I still ended up reading it mostly from beginning to end. There were times that I wanted to "skip ahead", but it does seem to be structured so that each chapter builds on the previous (this might also be because this is the first WPF book I've read.)
After reading the entire book, I do have to say that the order the material was presented is somewhat puzzling to me. For example, data binding is not introduced until chapter 16, after chapters on graphics and control templates.
I found it valuable that in the early part of the book, notes often refer to better ways to handle things that will be discussed later. One example is where he is setting the MinWidth and MaxWidth values on several buttons in chapter 4, but has a note referencing styles which are described in chapter 12. So many times, authors describe primitive ways to do something without referencing the better way. And then we copy the code and do it the hard way.
Unfortunately, the first bit of code I copied straight from the book had an error... The second piece of code I used was a nice reusable window template that I used as inspiration for a custom window style. It worked like a charm, but I did find a bug related to resizing the window.
I liked the writing style and generally found the book easy to read (when it wasn't easy to read, it was because of content, not writing style.) It has an extensive index. Given the caveats I've expressed, I recommend this book as both an introduction and in depth reference to WPF.