Since its enthusiastic adoption a year and a half ago, by Google, Six Apart, Wordpress, and of course the eminent Dave Winer, I think we can all agree that nofollow has done … nothing. Comment spam? Thicker than ever. It’s had absolutely no effect on the volume of spam. That’s probably because comment spammers don’t give a crap, because the marginal cost of spamming is so low. Also, nofollow-tagged links are still links, which means that humans can still click on them�“and if humans can click, there’s a chance somebody might visit the linked sites after all. Heck, if we really wanted to eliminate comment spamߝ”why don’t we just get rid of hyperlinks altogether?
