Bloggers and search-engine marketers are accusing the open-source WordPress project of spamming the major search engines, while at the same time being one of the advocates in an effort to combat comment spam in blog postings.
The discovery emerged late Wednesday when the blog Waxy.org revealed that thousands of articles about such popular search terms as asbestos, mortgages and debt consolidation appear on sections of the WordPress.org site while being hidden from visitors to the sites home page.
News of the search-engine gaming technique spread quickly on the Web. As of Wednesday evening, search results to WordPress.org pages with the articles began disappearing from Googles Web index. Yahoo Inc. followed suit Thursday, removing the WordPress.org pages from its index because of what a spokesman confirmed was "noncompliance to our content guidelines."
Google officials declined to comment on why WordPress.org pages had dropped from the companys index, but its Webmaster policies bar techniques that display different content to its crawler than to site visitors.
The article pages were still appearing in results on MSNs search engine as of Thursday afternoon, though WordPress appeared to have removed them from its site. Links to the articles returned a "page not found" error, though a cached version still showed the articles.
WordPress is one of the blog-publishing tools supporting "no follow," an HTML tag that Google, Yahoo and MSN are beginning to recognize in order to ignore hyperlinks included in the comment sections of blogs. Search spammers often insert such links into blogs in an attempt to gain higher search rankings for their sites since search engines consider link popularity in determining a sites ranking.
"This is a big deal given the fact that theyre supposed to be combating search spam, and [instead] they are generating it," said Danny Sullivan, a search-engine expert and editor of Search Engine Watch.
Matthew Mullenweg, the lead developer of WordPress who oversees the Web site, was unavailable for comment on the controversy. According to his blog, he is on vacation. But in a support forum on WordPress.org, he previously acknowledged that the site was hosting articles and Google AdSense ads from a third party in exchange for a flat fee.
AdSense is the name of Googles program for syndicating ads to content partners. In the ad model, advertisers bid on keywords in an auction and pay based on the number of clicks on their sponsored listings.
"Im not sure if were going to continue it much longer, but were committed to this month at least," Mullenweg wrote in a posting dated March 24.
"It was basically an experiment. However, around the beginning of February, donations were going down as expenses were ramping up, so it seemed like a good way to cover everything."