I believe that about 2/3 of our e-mail is now spam. I wonder how long it will take for the same thing to happen to weblog comments. One thing I know is that it's getting harder to recognize and fight them every week. Until recently I only got a couple of "texas holdem" floods of comment spam. They were pretty easy to fight by just denying any comment with words like "poker" in them. But recently it has gotten worse. I got floods with the most horrible content like incest, sex with animals and who knows what. And who are the victims? You, because you can now no longer talk about those subjects in your comments anymore.
Also new in the weblog spamming scene is trackback spam. Trackbacks are a mechanism to let another weblog know that you are talking about one of their posts on your weblog. If I would link to a weblog post by X, my blogging tool (WordPress) would find the link and send a message to X's weblog software. This message is called a trackback. Many blogging tools publish these trackbacks in a comment-like fashion, as does WordPress. What happens now is that spammers start sending fake trackback messages to all kinds of weblogs, including mine. These trackbacks contain some text and the link of the post where the trackback came from. And of course, these spame trackbacks contain links to the usual kind of content: gambling or porn.
The trouble with trackback spam is that the only way to fight it is either by a spam filter, or by disabling trackbacks. Comment spam can be fought by letting users type in special codes that are hidden in an image. This can't be done with trackbacks, because they are sent by blogging tools, not people.
The latest thing in comment spam land is the ass-kiss comments. Throughout the last week I've been receiving comments like "Lovely, informative site, thanks." Are those really from fans? Sadly, no. This becomes clear from the website URL that is filled in with the comment. Again, the usual stuff: porn and gambling. The problem with this kind of spam is that it's not immediately apparant that they're actually are spam (unless you know that your weblog sucks). And I don't want to block anybody to say anything positive about my work of course.