Cal Evans has been kind enough to provide the PHP World with a guide to migrating to PHP 5.3, which can be found in the TechPortal.
Make sure to read the Release Announcement as you familiarize yourself with the new features, and improvements.
As PHP developers download and start testing the biggest change to the language [...]
It is finally here. PHP 5.3 has been released and like we mentioned before (PHP Namespaces Is Not Years Away, Now In PHP 5.3). It supports Namespaces.