Sebastian Bergmann notes today that he has release this third beta version of the upcoming PHPUnit 3 release, a popular unit testing framework for PHP.
A list of features is available as well as a list of changes. You can install PHPUnit using the PEAR Installer.
PHPUnit 3.0 is the (coming soon) version of PHPUnit - both a framework that makes the writing of tests easy as well as the functionality to easily run the tests and analyse their results.