A decade ago, off-site SEO has been all about links. But it’s expected for search to progress, given that there’s a continuous evolution in web usage – which also has an effect on web marketing best practices.
“Social signals” is another trust and popularity indicator that search engines can use by obtaining available data from known social media networks/websites.
User behaviors, in terms of web usage, have been more exposed in social platforms, which is why this ranking factor has been somehow more relevant in determining popular content, personalities and brands.
Although it’s not applicable to every industry, and not really a factor that Google will most likely focus on, it’s still a signal worth pursuing (diversified traffic sources is always good).
Read More at: http://kaiserthesage.com/off-page-seo/