Social networking sites are a main traffic driver for a lot of media website. The questions is, which social network drives most traffic?
While Twitter may seem like the most obvious traffic driver to news site, Facebook, in addition to being the world’s largest social network, is also the largest contributor to the mainstream media’s websites.
Statista and Mashable has created a chart that measure the amount of traffic received through various social media such as Facebook, Twitter, Reddit, StumbleUpon and other social sites.
Facebook consistently sends all 10 publications the most traffic, the amount of referrals from the other three networks measured varies by new property.

Image Source : http://www.statista.com/topics/1164/social-networks/chart/1324/social-media-traffic-of-news-websites/