Rookie mistake, my apologies. At some point, I mistakenly turned on a requirement for commenters to authenticate with an ID. Thank you to Eric Mack for emailing me about this issue, and I apologize both to Eric and any other person that took the time to compose a response to one of my blog entries and then had to ditch it when they found they had to sign up for an account.
Test, Test, Test. Is this thing on?