For those that are fans of Chris Hartjes's book The Grumpy Programmer's Guide to Building Testable Applications", there's some good news - he's working on a new book more centered around effective use of PHPUnit.
Having written a book that shows you how to write code that is testable it seemed natural to write a companion book for that, to give people a better understanding of how to use some of the testing tools. To that end, I’ve started working on “The Grumpy Programmer’s PHPUnit Cookbook” to be released in early 2013 (I’m thinking end of January / beginning of February if everything works out). The book will be a collection of tips and tricks on how to use the gold standard of PHP unit testing frameworks, the mighty PHPUnit.
At the bottom of the site for the new book there's a signup form for the email list about it. Enter your info and you'll be notified as the release date comes.