The goal of this book is to teach web developers the basics of web design. It builds on what you should already know as a web developer in introducing the various aspects of design.
This book is an excellent idea since there are a lot of web developes who may find it useful to learn at least the basics of web design and this book makes use of what they should already know as a web designer in introducing web design in a more efficient manner than a more general book would - by assuming that the reader already knows web development. All the essentials of web design are covered with appropriate references to how the aspects of design work in similar ways to how development works so that the person working through the book will have a far better idea of what the book is saying that anyone would have when first reading any more general book on web design - since the book draws on the readers on experiences from the past and relates the new knowledge to it directly.
The most major flaws in the book (and they are not too significant provided you are aware of them) are the couple of places where the autor provides outdated information. For example on page 127 where he suggests index.html#news will link to <a> on the index.html web page - which only works in some browsers - rather than suggesting that it will link to <div id="news"> which it will link to in all browsers apart from Netscape 4.
Information about IE8 was written before the browser was released and the information discussed on pages 226 and 227 was the way that it was originally proposed to work prior to the browser release on 19th March 2009 (8 months before the book's publication on 19th November). Since the browser actually now works the opposite way to what the book suggests and DOES support the standards unless you put it into compatibility mode those two pages really ought to have been rewritten before the book was published. Surely the nine months that elapsed between IE being changed and the book being released was sufficient notice to make that correction. There is a reference to IE8 nearing completion at the time of writing on the first page of Chapter 15 which is probably about right for when the book was actually being written but surely that browser release was signifiicant enough that the appropriate sections of the book should have been updated to reflect the way that the released version of IE8 works rather than the beta that the author had access to at the time. That there is so much wrong information in the book about one of the most popular browsers currently in use certainly reduces its usefulness.