By selling there current generation of OSs on CD with absolutely minimal documentation Microsoft have created a market for books such as this one.
There are a lot of features of Windows XP (the OS not the methodology) that are easy to miss. We often tell people to go and read the manual when they ask questions to which we think they should have found the answers for themselves. Now, when a colleague expects you to be an expert on XP because he has heard that good programmers know all about it, you can tell him to go and read the manual. When he tells you there isn't one, just smile and tell him to read the missing manual.
The text is clean and easy to read. The screen shots are much better than most even if they are entirely black and white.
If you use Windows XP and like having hardcopy manuals this book will meet your needs.