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Last week I had over 1800 backlinks showing up in GWT.  4 days ago I had 20, and now I have 5.  I have a very diverse link profile ranging from social bookmarks to YouTube, to Business Listings (Yelp, etc), and they're all gone.  Clearly there is not a particular segment of my links that are being targeted here, they've all been completely wiped out.  My rankings have fallen, and where I was on page 1/2 for all my targeted KWs, I'm now on Page 3, 4, and 5.  There are no penalties showing up in GWT, so I'm completely at a loss as to what is going on.  Please help! Website is: http://brownboxbranding.com