http://googlewebmastercentral.blogspot.com/2012/01/page-layout-algorithm-improvement.html my traffic dropped 20%
New version of Google Panda 2.5.2 is active from Oct 2011. After this update google provide more search specific result.
66% drop for me, it seems they have put something in the new algorithm which penalises you heavily for having ads above the fold
Also be careful that you don't have "footer spam" — that is, multiple links in your footer area that are not really helpful and relevant to that page. In other words, links that are obviously there for SEO purposes only. Google Panda has hit this hard. I had footer spam (inadvertently), got slammed in the early Panda, removed all my footer spam, and all my traffic came back afterwards. I will admit it was a good improvement by Google in its algorithm.
I had 3 ads above the fold (Adsense + BuySellAds). 50% drop in traffic! Keywords went from Top to nowhere!
Hahahaha Nice!! I have actually dodged the bullets - while I don'r have footer spam, I have my relevant tags there... and the sitemaps and shit... I use my tag's like categories and since adding them - I have witnessed an increase in traffic... I am still on the up. I like the Panda!! I want to give him a cuddle and a pat
Google has always stressed as long as you have unique quality content, and quality backlinks you have nothing to worry about
Few years ago people thought "Smart Pricing" and "Sandbox" are the worst things that can ever happen to a webmaster and then "Pandas" and "Partons" showed up
Haha! Btw I'm surprised your site has been hit by the this new algorithm too! It didn't have so many ads (above, below or in between) :/