"This weblog has a comment spam detection system based on simple heuristics. Comments are assigned a score; if the score exceeds a certain level the comment is placed in a queue for moderation. As of today, one of the heuristics is â€œdoes the comment author have an OpenID that is on the whitelistâ€. Iâ€™ve populated my whitelist with the OpenIDs of people who have posted two or more useful comments and do not appear to be using an anonymous provider. Iâ€™ll be adding to it regularly in the future. Here comes the social part: Iâ€™m sharing my whitelist. If you run your own OpenID-enabled weblog you are welcome to include my whitelist in your comment spam heuristics. If you publish your own whitelist, I will happily do the same. Social whitelisting benefits from being de-centralised, just like OpenID. If I find that you have whitelisted a spammer, I can unsubscribe from your whitelist. Thereâ€™s no central authority or point of failure."