On the PHP::Impact blog, there's a new tutorial showing how to use the Phing build system to deploy your application.

A common way to automate development and deployment tasks is by writing shell scripts, however, Phing provides some advantages over shell scripts for task automation. [...] But, having a large collection of shell scripts can lead to a maintenance nightmare, reason why I decided to port some of them to PHP as Phing tasks. I chose Phing because it's simple, powerful and very easy to extend.

He talks about DbDeployTask (an optional task for database revisions) and how to use the system for Agile development practices.