Human Spam

The spammers are paying humans to spam instead of having bots do it. This means the spam is time-consuming to detect as spam, because it isn't obviously spam. And it almost always gets past the spam filters.

This is typical:


The comment is perfectly reasonable, almost useful, and posted to an article where it's relevant. But the link? Spam.

Unless you get enough commenters to make croud-sourcing spam filtering work (think Slashdot or Digg), it's up to the blog owner to do it.

I'd just shut off comments altogether, but some of my posts have dozens or hundreds of valuable comments and I'd hate to lose that.