В апреле Google зарегистрировал 2 новых патента на алгоритмы ранжирования:
http://www.free-seo-news.com/newsletter263.htm#facts

While that information was already available in previous patents, the new patents indicate that Google could also look at the following factors:

• The rate at which ads are shown and updated on a web page over time.
• The quality of the ads. For example, a web page whose ads link to web pages with a high TrustRank may get a higher score than pages whose ads lead to untrustworthy sites.
• The click-through rate of the ads.

Googly might track and analyze web page characteristics that change over time, including ad traffic, to calculate a score for that page.