Guyren Howe has considerable experience with both MySQL and PostgreSQL. He discusses the myriad technical and other advantages to using PostgreSQL instead of MySQL for, well, pretty much anything.
RubyTu.be is a community driven collection of Ruby related videos and screencasts. Questions? Comments? Contact RubyTu.be via e-mail or click on the Feedback GetSatisfaction widget found on the other side of the page.