The title should be "Overview Of Building Scalable Web Sites".
I give it 2 stars not because it is a bad book but because I was tricked into thinking it was going to be useful as a scalable website builder. What you should do is look at the table of contents and research those topics and not bother reading this book.
The book is more of an overview of the topics you need to consider when building scalable web sites. For example, if you are building a scalable website and the powers that be put someone who knows nothing about web sites in charge of managing you, this really is the perfect book to give to your new manager. Your new manager will get a clue, but your new manager won't know a thing about HOW to build anything, but will know ABOUT what is being built.
The thing that got me is the first 188 pages of the book, just doesn't seem all that useful. On page 1 there is a definition of "What Is a Web Application", I'd estimate a book like this should assume you know what it is (it even suggests you do know what it is), but probably should save space and not even bother writing about it.
Some sections and my summaries:
Layered Software Architecture - could summarize into: DB layer, app code, html, css on top
Layered Technologies - get appropriate book on actual topic such as DB book, and use a template language
Getting from A to B - separate program from markup, use a template system
Hardware Platforms - dedicated, co-located, self hosting, space/power consumption, networking
It took 26 pages to get through all of that. Indeed they are all very important topics (for the web builder and your new manager to know), but as a builder (if you've gone past the first "hello world" website) you should really know that you'll be using a database and writing web app code and using html and css. You should already know that in order to run a website, you'll need to run it on a computer which takes up space and power and needs to be networked. It's good to know that dedicated/colo hosting exists, but no need to write so much about it.
It's almost like a book titled, "Building huge skyscrapers" and then goes on to say you are going to need construction equipment, concrete and steel. You'd hope the person interested in that book has already built houses or commercial buildings and has used construction equipment and concrete and steel already. I'm probably being too harsh here, but that's the jist of it.
My "favorite" chapter is 3, "Development Environments". Use source control, have a good build system, track bugs. Those are very good rules, but to have 19 pages on source control AND 3 of those pages on RCS/CVS, it's like, "Are you kidding me? Isn't this book about building scalable websites?". Nowadays people probably have never even heard of RCS... (the book is a bit dated though).
Chapter 9, Scaling Web Applications has some stuff about load balancing and database replication/master-slave info, but after reading the chapter, you still won't have the first clue of what load balancing system to use or how to setup database replication or clustering... but you'll know that load balancing and database replications exists and know a little about them.
The actual best chapter is chapter 10, Statics, Monitoring and Alerting, there is information there that is useful. For your own sake though, look at the Nagios, Zabbix, etc monitoring packages and that'll get you started in the right direction.
For the reviews which say this book is technical, I couldn't disagree more, if it was actually technical I wouldn't be so annoyed with this book. If it was technical, then you'd know HOW to do something after reading it...
In conclusion, I think it's a good overview on the topics involved, but it's not really about building anything, it's about some topics you need to know that are involved with building a scalable website.