We've had a couple of reports from readers of problems with our comment CAPTCHAs (the word-number combinations you have to type to prove you aren't a robot when posting comments), and while we think we could probably weed those out, we are getting a lot of spam comments even with that system in place. So we're going to switch over to comment moderation, at least for a while, to beat back the spammers. This means you may have to wait a few hours to have your comments approved, but you won't have to fill out a CAPTCHA.