A webpage that shows a lot of social shares appears much more authoritative as compared to a webpage with few social shares. This has been corroborated by research data that shows content activity from social media channels weighs into rankings on search engines. The importance of links as a ranking parameter is less likely to cease as they evolve into a new role that indicates the importance of social media activity as a ranking factor.
Here are 20 social signals that Google tracks to determine ranking based on various social media activities on Google+, Facebook, Twitter, Pinterest, Reddit, Digg, StumbleUpon & Foursquare. http://goo.gl/wBvVDM
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