They found me. I don't know how, but they found me. No, I'm not talking about Emmet Brown's Libyans. I'm talking about comment spammers.
When you think about it, it's surprising that my blog could be around for eight years and remain mostly spam-free with no more that a couple simple checks on comments to ensure that the text doesn't include urls or any of a number of spam keywords. It was only a matter of time until somebody wrote a spambot script to match my comment entry form. And now my options are to rename all my fields, or manually approve all comments. Given that either involves some coding effort, but one of those is a temporary solution at best, I'll probably code to manually approve comments.
So for the time being, if you comment you'll likely get a "COMMENTING TEMPORARILY DISABLED" message, but given changes I made a couple days ago, I'll be able to see your comment, and I'll make sure it gets online if it's legit. When I get some time, I'll change the message to indicate that comments will need to be manually approved.
This is the pain of having a self-coded blog.