When it comes to crowd-sourcing content through the suggestion page type, our users are naturally concerned about spam. I recognize that you've got a "Rules" system (for flagging and warning, and deleting identified spammers). Are there other spam-protection measures in place? Anything like Mollom? (I notice you don't use any sort of CAPTCHAs.) What is the user/admin experience like, in terms of spam in NationBuilder? What barriers are there to spam?
Yes, we use various techniques for spam protection that have proven to be far more effective than CAPTCHAs, which are a horrible user experience. We don't talk about what they are though for obvious reasons.
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