PHP Books

I'm planning to "kick it up a notch" with learning PHP in the coming months. Just ordered this book (Programming PHP 2^nd edition) should be getting it in the next few days. Also since it is just above $25 you get free shipping (in the US and UK, in Canada you will have to  purchase an additional item, hey...). Assuming all else is equal (reputation and topics), I usually pick books based on 3 criterias:
- Popularity
- Reviews
- Published date

Following these 3 parameters "Programming PHP" is the best.

Programming PHP

Book description from Amazon:
Programming PHP, Second Edition is the authoritative guide to PHP 5 and is filled with the unique knowledge of the creator of PHP (Rasmus Lerdorf) and other PHP experts. When it comes to creating websites, the PHP scripting language is truly a red-hot property. In fact, PHP is currently used on more than 19 million websites, surpassing Microsoft's ASP .NET technology in popularity. Programmers love its flexibility and speed; designers love its accessibility and convenience.

As the industry standard book on PHP, all of the essentials are covered in a clear and concise manner. Language syntax and programming techniques are coupled with numerous examples that illustrate both correct usage and common idioms. With style tips and practical programming advice, this book will help you become not just a PHP programmer, but a good PHP programmer. Programming PHP, Second Edition covers everything you need to know to create effective web applications with PHP.

More information on Programming PHP 2^nd edition: