Sam Ruby has already posted a simple patch to MoinMoin that implements Google’s proposal for a new link type for the rel attribute for the HTML anchor tag. The HTML specification supports the definition of new link types, as long as the author implements a profile. Google has proposed a “nofollow” link type, which will instruct the googlebot website crawler not to follow links with that link type.
The reason for the new link type is that spammers are taking wanton advantage of weblogs, wikis, and other types of websites that allow anyone to post text that either includes embedded HTML or is converted to HTML. While there is obviously some value to the spammers in spreading their message via simple text form (otherwise, why would they send out all those emails), the primary value is in creating inbound links to their porn, pharmacy, whatever sites. Search engines crawl the links on the blogs and wikis back to the spammers’s sites. Since many search engines, and especially Google’s, use the number of inbound links to assign a rank to a web page in relation to certain keywords, the spammers views weblogs and wikis as fertile ground for boosting their search engine rankings. Most people don’t go past the first couple of pages of search results, so it can make a huge difference for a spammer if they can make it to near the top of the search results for commonly searched on keywords.
I’ve held off on linking from this blog to information on my Wiki out of fear that spammers will find my wiki and attack it. Though applying Sam’s patch to my wiki certainly won’t dissuade a spammer’s robot from attacking it, at least they will get less value out of it. And that has to count for something.