Google announced a new algorithm change that looks at your page layout and if the ads above the fold are excessive, your site can be penalized and downgraded in the search results.
This comes with no surprise to me and others, because 10 weeks ago, Matt Cutts announced that this is something Google is working towards.
We've heard complaints from users that if they click on a result and it's difficult to find the actual content, they aren't happy with the experience. Rather than scrolling down the page past a slew of ads, users want to see content right away. So sites that don't have much content "above-the-fold" can be affected by this change. If you click on a website and the part of the website you see first either doesn't have a lot of visible content above-the-fold or dedicates a large fraction of the site’s initial screen real estate to ads, that’s not a very good user experience. Such sites may not rank as highly going forward.
Google released a special tool at browsersize.googlelabs.com to help you visualize if your site may or was impacted by this. Here is how this site looks (click on it for a larger view):
We seem to be okay, but what about Google's own search results. Well, Google won't let you plug in their own URLs into the tool, so it is hard to tell but I doubt they would pass the test.
Danny Sullivan, as well as many others, go through the hypocrisy with this new penalty and how Google is doing the exact opposite. Not only that, they recommend to their AdSense customers to place ads top heavy so users click on them. Here is their ad map:
That being said, the algorithm is out, if you were hit, you would probably know by now. To fix it, remove some of those ads, and wait and wait until Google pushes out an update. It can takes weeks.
If you decide to update your page layout, the page layout algorithm will automatically reflect the changes as we re-crawl and process enough pages from your site to assess the changes. How long that takes will depend on several factors, including the number of pages on your site and how efficiently Googlebot can crawl the content. On a typical website, it can take several weeks for Googlebot to crawl and process enough pages to reflect layout changes on the site.
Who is affected? Google said 1 in every 100 searches are.
If you read the forums, almost every thread talks about how Google is doing one thing and saying the other.