PHP - Test Driven Development

Today, Sebastian Bergmann , the developer of PHPUnit , came to our company, represented this very useful thing and besides test driven software development as a whole. I wonder how web developers relate to this approach? The fact is that our company, or rather, the portal is on the verge of a completely new development from scratch, the old functional system does not cope with just 3 million users, and it is difficult to write innovations, and it’s hard to figure out where the ignorant is a dense forest. We decided to use the Zend Framework as the basis and at the same time to do everything in a fashionable way - Unit Tests, Pair “extreme” programming ... Napoleonic plans, marketing gives time to Christmas. A representative from Zend will arrive tomorrow, listen to the wishes and answer questions.
At dinner, Bergmann told funny facts about the PHP Olympus giants. He now works (only one day a week) on eZ Systems in Norway, participates in integrating PHPUnit into the new Zend Studio Neon, which will be based on PHP Eclipse and bring with it a bunch of useful features, such as embedded JS debugging, etc.