Andy Baio posted in March 2005 about this: "Wordpress is a very popular open-source blogging software package, with a great official website maintained by Matt Mullenweg, its founding developer. I discovered last week that since early February, he's been quietly hosting at least 168,000 articles on their website. These articles are designed specifically to game the Google Adwords program, written by a third-party about high-cost advertising keywords like asbestos, mesothelioma, insurance, debt consolidation, diabetes, and mortgages." source: http://waxy.org/2005/03/wordpress_websi/

Matt acknowledged the issue with this content (cloaked with CSS) and apologized the next month: http://ma.tt/2005/04/a-response/