It seems that the spam-master is nothing if not persistent. It continues to probe my defenses even though my latest Comment Spam counter-measure has locked it out so far. Here’s the recap of my current defenses:

1. Both robots.txt and the robots meta tag are used to prevent the indexing of comments. Presumably eliminating the motivation for comment spam [although that didn’t deter my adversary].
2. Tag moderation prevents links from being displayed until the comment is approved [which also did not deter my adversary].
3. Outbound link blacklist blocks comments that link to known bad sites.

I hope that my defenses continue to hold - the next step from here is adding support for the MT-Blacklist Master Blacklist.