Rating: 

I was impressed by the clarity and conciseness of this little book. It was a pleasure to read and I had no problems identifying the places that I did not have to read on the first reading, or that were related to PHP 4 and did not need to study fully.

The examples about PHP 4 (that are then recreated in PHP 5) are carefully chosen to explain how the new language makes things easier and/or more effective and modular with PHP 5. This didactic device is very useful for people that have worked extensively on PHP 4.

This is clearly not a book for people that are just begining on PHP or for those that have little experience on PHP 4. It is better for them to learn from a PHP 5 book (Learning PHP 5 maybe?) directly. However I'd recommend anyone on that situation to then come back and give this book a careful look since many topics are explained here better than in many other places in the literature.

I was especially fond of the chapters on XML, Iterators, and Streams and Wrappers. However all the other chapters were very helpful and I can see myself coming back many times in the future for clarifications on fine point on OO programming, MySQLi, or Error Handling.

One of the best O'Reilly books I own.