Here is an interesting article: You may think this has to do with Penguin et al. However, this article is from June 2, 2009!!!!!! So, please do not buy into the "Google are smarter than us, they have all the best brains in the world" crap. Yes, the collective intelligence of hundreds if not thousands of Google engineers is greater than mine and yours. But the collective intelligence of tens (if not hundreds) of thousands of marketers like you and me are far greater than theirs! TL;DR: Stop believing BS and keep hammering!!