I’ve noticed something. At least I think I’ve noticed something! There are people out there who look for neglected blogs and post spam comments on them. I can see the logic: The comment will get posted and since the blog has been neglected for some time (no new posts by the blogger), the said blogger will not be checking.
This means that the comment with its link to who-knows-what will stay on the blog with ligit posts and comments and, in their minds, increase Google rankings, and click-throughs to their site(s). Read more