Since switching this site to the Intense Debate (ID) commenting system, one function I missed was the ability to integrate reCAPTCHA1 into my comment forms. While I understand some are not fans of the system that adds nearly inscrutable text to a form that then must be typed in to the accompanying box to continue, the mechanism does significantly reduce the volume of comment spam.

After contending with a few hundred spam comments daily, all of which seemed to escape the Akismet and banned-word filters already present in Intense Debate, I contacted support to suggest that a CAPTCHA system be offered as an optional feature.
As the following response to my inquiry indicates, no such system is planned for Intense Debate. Instead, the people at Automattic (the company behind WordPress, Intense Debate, and Akismet) are working to improve Akismet’s effectiveness, an endeavor that, if successful, will benefit anyone using the spam-filtering service, not just the users of Intense Debate.
Currently we do not offer a reCaptcha option. However we have found that reCaptcha is not a long-term solution to spam, in fact it’s becoming less effective than ever because it’s cheap for spammers to pay people to fill out reCAPTCHAs all day long. Solutions need to be content based, like Akismet is, and we’re currently working with our colleagues at Automattic on enhanced Akismet integrations.
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Michael Koenig
Intense Debate | Automattic
While I have nothing but anecdote to contradict the assertion that spammers are willing to pay people to complete CAPTCHAs for them, I certainly had less comment spam when such a mechanism was in place. That notwithstanding, the features offered by Intense Debate are important enough that I intend to leave the system in place.
- reCAPTCHA is one form of a challenge system, known as CAPTCHA or Completely Automated Public Turing test to tell Computers and Humans Apart, developed at Carnegie Mellon University. More information is available on Wikipedia. ↩
Thanks for sticking with ID. While it might not be ideal, one way to cut down on spam in the meantime would be to require an IntenseDebate account in order to post comments. Is this something that you've considered?
I took another look at your moderation/blacklist settings and I'm looking into a possible issue with your blacklist. I'll let you know what I find.
I may require authentication to comment. I was hesitant at first because I worried it might drive away readers, but integration with OpenID, Twitter, and Facebook, on top of Intense Debate authentication, should avoid that problem.
Thanks for looking into the blacklist issue.
Erick