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Hi, As you mention Panda is not a link based update so it is unlikely that the links are related to your issues, if (an important if) you are sure your problems are Panda based. Check out this useful analytics overlay tool to see if any important dates pop out of your analytics data and confirm traffic drops around known google updates. As Guillermo mentions, reciprocals in themselves are not inherently bad and as you say they have brought you direct referral traffic so nothing wrong with that. That being said, bunches of them on 2000+ pages, especially if they are anchor text rich and do follow could be a fine line. If in doubt I would no follow them, but make sure you have identified as best as possible the original cause of your problems before you start making wholesale changes.