While the title of this book refers to the "Modern Web", the content of the book uses very outdated techniqes. While it gets a five out of five from me for what to consider in your design, it gets zero out of five for how to implement that design. Of course the what and the how are not equally important and so that doesn't result in a rating of two and a half.
This book reminds me of Joe Burn's book "HTML Goodies". In both cases the author has been thrown in the deep end to teach a subject that they know nothing about and has had to learn as they go. In both cases they have used what appears to work rather than learning the right way to do it. In both cases they have written a book about what they have learnt. In both cases the approach that they have taken to coding is far from being the right way. Joe's book is now looked on as a good set of examples of how not to code a web page. Perhaps Penny's book will end up being looked at the same way.
In some ways this is unfortunate because Penny seems to really understand what needs to be taken into account in both the analysis and design phases of creating web sites and is only let down in the area of how to implement the design. The word "Modern" in the title is certainly a misnomer when you consider that many of the techniques presented were considered to be outdated several years ago.
I will admit that unlike most of the books that I review where I read the book through from cover to cover, I only got about a third of the way through this one and so perhaps the rest of the book is better. Unfortunately the first part of the book contained so much wrong information that I just couldn't bring myself to read any further.