I thought this was a good bit of information...
IMO Google is working on signals. Google algo is mainly based on user experience now, thats my opinion and I strongly believe it.
f (ranking) = a1 x f (onpage) + a2 x f (offpage) + a3 x f (demographic user experience of the page)
a3 > a2 > a1 (a3 looks much higher than a1 and a2 now).
Search in google for <a certain competitive phrase> and see the results
<search links removed>
All three shows you different sites. The site that is #1 in India is #96 in Google.com. Similar difference can be seen. I have been watching this for almost a year.
I think f (demographic user experience of the page) is playing a big part in the complete algo. Now the big question, how is google collecting user experience, as it can't be just related to SERP clicks? Here is my opinion,
Google Toolbar: Privacy says, "In addition, we use log information about aggregate Toolbar usage to improve the quality of Toolbar and other Google services."
Google Analytics: Privacy says, "We may also use personal information for auditing, research and analysis to operate and improve Google technologies and services."
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