mcskoufis - 7:34 am on May 16, 2013 (gmt 0)
I can confirm that on 6th march a major brand website got hit. This is not a client I manage, I just do some analytics tasks, so have access to see what is happening.
This site got hit hard in 2011, recovered in 2012 and now plummeted to more than 70% fall. Thats thousands of visits less a day for them and still hasn't recovered. They were involved in some very silly backlink schemes in 2011 and seems that they've done something in 2013 that destroyed the site's organic performance.
It is a Greek site and their "SEO" was leaving comments in USA & UK "SEO blogs" with obvious manipulative anchor texts to the client who is totally unrelated of course :)