The game has changed.
Now, in 2013 and beyond, Social Media is playing an increasingly important role in how your blog content ranks in Search Engines.
'Social signals continue to correlate very well with better rankings' – SearchMetrics'
SearchMetrics found that Google +1s, Tweets, Pinterest shares and all Facebook activity (shares, likes & comments) had a significant correlation to higher search engine placement. In fact the only non-social measure in the top 8 correlating measure was the number of backlinks.
And it looks like social media signals will become increasingly important to SEO for the foreseeable future.
Via Antonino Militello