aristotle - 6:13 pm on Aug 30, 2012 (gmt 0)
I'm not an SEO professional and really don't have time to study your site or situation in detail. I also know that Penguin is based on a false premise (SEO=spam) and is flawed as a result. In fact it's very possible that your site has been unjustly penalized and is part of the collateral damage. Yours certainly wouldn't be the only one. But I don't think you should worry about wiki and DMOZ spam clones. I strongly doubt that's the problem. Maybe the Google algorithm thinks you might have purchased some links. Maybe the distribution of your backlink anchor text looks suspicious. Maybe your site acquired backlinks at an unnaturally high rate. There are a lot of people who are puzzled as to why their site was penalized.