Well, I guess I’ve “arrived” here at the new location: the first three comment spams (all for the same reprehensible bunch of wankers) have been shoveled into the database.
WordPress has a resident spam tool called Akismet; this is my first experience with it. (My other WP sites are treated with SpamKarma.) Akismet duly isolated the infection and shunted it off to the waiting room at Deletion City, exactly as I’d hope. I have yet to port over my collection of Dubious Words from the previous platform, but I’m not in any huge rush.