Probably first public announcement of 2012, Google just launched an algorithmic change that targets at the layout of a webpage and the amount of content one see on the page when landed on a page after clicking on a search result.
In short, the sites that don't have much content "above-the-fold" are 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, such sites may not rank as highly going forward," warned Matt Cutts.
Cutts further writes, "this algorithmic change affects less than 1% of searches globally. That means that in less than one in 100 searches, a typical user might notice a reordering of results on the search page."
Adding, he notes, "This algorithmic change doesn't affect sites who place ads above-the-fold to a normal degree, but affects sites that load the top of the page with ads making it hard to find the actual original content on the page. This new algorithmic improvement tends to impact sites where there is only a small amount of visible content above-the-fold or relevant content is persistently pushed down by large blocks of ads."
If you believe that your website has been affected by the page layout algorithm change, consider how your web pages use the area above-the-fold by either using Google's Browser Size tool, or others, to see how your website would look under different screen resolutions.
"When you 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," Cutts said. Adding, "It can take several weeks for Googlebot to crawl and process enough pages to reflect layout changes on the site, as it depend on several factors, including the number of pages on your site and how efficiently Googlebot can crawl the content," he said.
Also, while releasing the 'above-the-fold' ad specific page layout algorithm to penalize sites with heavy ads on page, Google's double-speak contiunes, as the companies advertising deaprtment AdSense sent an email on the same day encouraging publishers to put more ads: (see the pic below that AdSense team sent with the email and a video below, released on January 18)
"In this video from Inside AdSense, etitled "AdSense Tips: Place up to 3 Content Units Per Page", we'll walk you through how to best implement up to three AdSense for Content ad units on your content-rich pages," reads the videos description page:
Also, watch the video of Live Q&A September 21, 2011 with Cutts:
Finally, if you are confused with Google’s double speak, watch this video created by Common Craft from SEL, that in just three minutes explains "what search engine optimization?" and other such questions: