Looking back over our stats, I just discovered that we added ads to a large number of our pages the day AFTER Panda 1.0 (stroke of brilliance right there!) We were not affected by Panda 1.0. We were however affected by Panda 2.0. Although it was only one ad on the page, my theory is that these ads often appeared on pages with quite thin content (ie just one result). Maybe that thin content was considered ok without ads. But with an ad, not so good..
But ouch, if those ads we added were to blame, that's a seriously hefty price we've paid for adding Adsense. I've cleaned it up now so ads don't show unless there's a bunch of results and also ensured that the thin content won't be indexed. Here's hoping it helps.
These are [very local] listings. Many small towns only have one option. The ad was a 300x250 block off to the right. So it has three ads inside it.
Later in 2011 we even added more ads (trying to offset some panda losses). These were at the end of results (and formatted similarly). Fine when there's ten, but when there's only one it meant one result + one ad. Plus the ad on the right. Definitely the balance of the page was more ads than not. And there are actually quite lot of little towns with only one property so the percentage of pages with thin / ad filled content did not look good. Or so my theory goes at least.
[edited by: tedster at 9:56 pm (utc) on Jul 9, 2012]
Well I have some news to report that may help some people.
About 10 days ago I removed a single large block of adsense from one of my sites. It was one of the large square blocks, placed atop the content, front and center. The site has been struggling quite a bit for some time, though I didn't know why.
It's a quality site and has had great rankings in the past. I haven't changed anything on the site in at least 6 months. 10 days after removing the ads, I got all my previous rankings back. My traffic has tripled ( from 500 uniques per day to 1500). It's conclusive to me that ads can definitely hurt you, and very badly.
Over a year ago but it did not coincide with any panda date. The site actually went up after panda. Nothing changed with the announcement of the above the fold ad penalty from earlier this year though. It's hard to be 100% sure about all these things but all I know is I removed the ad and it's the only change I made.
Just some info for people that it's worth trying removing all above the fold ads and see what happens.
You could see about a paragraph of text above the fold. However, based on "quality" or whatever, it was clearly ad focused. You did pretty much have to scroll to start reading. The top logo is somewhat tall in my opinion which possibly did not help - at 160 pixels tall.
The site has a pretty good layout and design and content - people definitely read it, average visitor time on almost all pages is 4-6 minutes.
I assume that there's an indirect correlation between #of ads and ranking. When removing ads, site speed increases. A speedy site makes the visitors happier and they tend to stay longer and navigate more on the site. Time on site and page/visit are direct signals to ranking - These are the factors that may impact site's ranking.
Gouri, I see no change in crawl data around the time rankings returned. I'm not really sure the answer.
What I do know now is that I put the ads back up on the site about 10 days after rankings returned. I just went back to "panda" levels over the past 2 days. So I'm down about 66% in traffic. I've removed the ads again and I will update if and when I recover again.