There is a great deal of buzz about Google (and presumably other search sites) using the 'rel="nofollow"' feature to combat comment spam. The idea is that if your comments have this tag on them, they won't get indexed, and therefore comment spammers will stop or slow down their spamming.
Er, has everyone forgotten the lessons we have learned in the past ten years about Usenet and email spam? Those communities have already implemented much more powerful technologies, and the level of span keeps increasing. The blog world is immune from this reality for what reason...?
Chuq describes well why this isn't the answer. Sure, it will help somewhat, temporarily. The comment spammers who are doing it by hand may be somewhat thwarted, but they are probably a small fraction of the comment spam we are seeing today, and would become an even smaller fraction over the coming year. His point that few people update their software is particularly apt: the better bloggers will do so, but they are in the minority, so comment spammers will have so many targets that they'll keep it up for years.
Fact: anything spammers can do to automate their activities, they will do so aggressively. Quite frankly, even if they never got a drop of "Google juice" for comment spamming, they would continue to run the spambots just for the people who read the comments. Why should they not?
The only ways to prevent comment spam are to not have comments (like here), or to have comments allowed only from people whom are allowed to post comments though human-controlled vetting. That vetting can be done early ("OK, you can comment anywhere"), or on a comment-by-comment basis ("I have to accept any comment in the queue"), but any automation of the process will simply open you to spam eventually, always sooner than you expect.
Posted by lookit at January 19, 2005 10:20 AM