Filtered Comments

A number of people have suggested using Bayes filters or other content analysis in order to defeat comment spam. The problem with this approach is that comment spam is a different animal that email spam. At this point in time (although it may change), the purpose behind comment spam is to add the spammer’s URL to your site. By sprinkling their links over hundreds or thousands of pages, they hope to increase their search engine rankings.

The messages themselves are always short, innocuous comments. Some of the ones I’ve seen make an attempt to appear to be a valid comment by copying verbatim the contents of someone else’s comment.

Since there is nothing spammy about the text of the comment, content filtering won’t do any good.