Akismet is an anti-blog comment spam service developed and run by Automattic, makers of WordPress. The service sounds a lot like what MT-Blacklist wanted to be, a central repository solution, but with fancy scoring, and proper scalability (or so they claim). It works with WordPress, Movable Type, and many others, and has an open API for integrating into other software like web message boards. And it's free for personal use.

Strangely, the day I installed Akismet, I started getting unusual comment spam consisting of random-seeming collections of letters in short word-like formations, with no human-usable information or URLs. I'm guessing they're probes for vulnerable forums, where a site's vulnerability is easily tested by performing a search for one of the random strings. (I assume similarly for the "My coworker just bought a car for $#####" spams, where ##### is a random number—but only because I can't think of a better explanation.) I doubt my own theory on the grounds that there are other ways to test the effectiveness of spam, and that it doesn't seem necessary to scrub lists of blogs for effective targets, since it's so cheap to blanket them all. But I don't really know.

In any case, the randomness and lack of typical spam payload (URLs) makes them especially elusive from Akismet's anti-spam strategy, so I'm still stuck moderating them despite the newly installed plugin.