Very good book for intermediate or advanced php developer, I'm very happy with the book.
Ruslan

This book is geared toward the intermediate PHP developer who wants to bring in aspects of OOP, Testing and Refactoring to help improve the quality of the code they write. It is split into four parts; Basic Tools and Concepts, Testing and Refactoring, Building the Web Interface, and Databases and Infrastructure.

In addition to PHP, I have decent amount of experience with Java and Java web frameworks such as Struts. So as I worked through this book much of the content was familiar to me but from a Java perspective. It was enlightening to see the authors express these same concepts from a PHP perspective. The fact that many times (not always), the implementation in PHP is more concise and elegant that the Java alternative really shows of the power of a dynamically typed language such as PHP. Also the fact that PHP was bred from the beginning to be a web development language gives it a definate advantage in the web arena.
The authors are honest though, they haven't simply painted implementing OO, TDD, and Refactoring as completelty painless. For instance in the testing portion they've devoted quite a bit of time to showing the difficulties of testing (especially in a Web environment). Such as the need for mock objects and the difficulty in keeping mocks "real enough" so they fail and pass as the real object would. This full disclosure is key for readers to estimate if the extra effort of a concept is worth the benefits for their particual situation.

Overall this is great book for the intended audience. It is not "black and white" about the solutions it proposes. Reasonable alternatives are given and the pros and cons of each are expressed. For those with extensive OO experience, some portions of the book may seem trivial but overall it is still worth a "quick scan" to see the specifics of PHP implementations of general OO concepts.
PHP in Action: Objects, Design, Agility

The problem with PHP experts is that they're just beginning to catch up with experts in other OO languages. The author purports to compare and contrast Java and PHP in early chapters, but fails to point out a significant difference, although he uses such examples over and over: that object constructors that take no arguments may omit the (empty) parentheses in PHP, but not in Java. The author's explanations of certain design patterns are sorely lacking; for instance regarding the Strategy pattern, he uses the ambiguous term "pluggable" over and over but never once the term "algorithm", yet substituting algorithms is precisely what the Strategy pattern is designed for. There is some very good material on MVC -- he even has the courage to contradict Martin Fowler -- but mixed with suggestions that are myopic, such as the author's continued insistence that using PHP's various ob* (output buffer) functions are practically the only way to compartmentalize web page components should you choose to role your own framework, while ignoring the notion of layout definitions (a la Java's Struts/Tiles), which I am using successfully on a current project. So, while this is a much better thought out book than most on PHP, this needs a highly critical reading, something which most PHP programmers are probably not inclined to.

This is definitely the best book I've read in the programming world. There are some very good PHP books, but this is so far the best. Why? I have a MS in English Lit and some of the books I have read have left me furious over the poor quality of the editing and general sloppyness. Not so here! Amusing at times but not self-involved. Appropriate for an adult. A clear intent to educate that succeeds!
Good job.
PS - Almost done and no typos!

By far my favorite PHP book and the one that I recommend to everyone who asks me about improving their PHP knowledge.

The book not only covers what you should do, but it goes into explaining why and how in an easy to understand manner. Highly recommend to anyone who understands how to script PHP but now wants to learn how to become a PHP programmer.