Nofollow
I’ve updated this WordPress installation to automatically add the rel=”nofollow” tag to any links in the comments. This is part of an attempt by Google and the other search engines to change the economics of comment spam and discourage the spammers:
From now on, when Google sees the attribute (rel=”nofollow”) on hyperlinks, those links won’t get any credit when we rank websites in our search results. This isn’t a negative vote for the site where the comment was posted; it’s just a way to make sure that spammers get no benefit from abusing public areas like blog comments, trackbacks, and referrer lists.
Since all the major players in the blog hosting world are going along with this, it seems like a good idea to me. Many of the privately hosted blogs, like this one, were taking fairly stringent measures already to deny comment spammers the benefit of their viciousness, but since most bloggers are on hosted sites and either don’t have the time or the expertise to do much about comment spam, our efforts didn’t really have any effect on the payoff for spammers searching for page-rank. If Google and the other search engines, though, can systematically deny comment spammers the benefit of their links, particularly in the huge arena of the hosted blogs at places like Blogger, LiveJournal, TypePad, etc. that could really put a dent in the effectiveness of comment spam as a technique. I don’t think anything will change immediately, since there’s not much benefit to the spammers to change their existing scripts, but if the sites that are trying to pull traffic start falling in rank, that could change. Certainly fiddling around in the margins (the blogs that do take active steps to prevent comment spam) was never going to change anything, and more and more blogs were giving up on allowing commenting entirely, since even the effort of moderating the posts was getting to be too much. I just deleted over 1600 spam comments on this blog; they never made it past moderation, but if I hadn’t hacked my moderation page to make the default action “delete”, it would have taken me hours.