According to a Q2 report by Brightcove and TubeMogul labeled “Online Video & the Media Industry”, the most referred video online came from the social networking sites Facebook and Twitter.

Not only that, but social network viewers watched video longer compared to viewers who were referred to video from search sites such as Google and Yahoo! One minute and 47 seconds to be exact, whereas Google viewers watched video for one minute 34 seconds and Yahoo! for one minute 27 seconds.
Word of mouth is long believed to be one of the best ways to get information and in an article by MediaPost
News, Jeff Whatcott of Brightcove was quoted saying: “It used to be all about search. But Facebook and Twitter are becoming significant traffic drivers, since social networks are increasingly how people are discovering video.”
Speaking of video referral traffic, Facebook is growing at an average monthly rate of 48% and Twitter at an average of 38.7% followed by 35% for Yahoo! and 15.5% for Google, according to the Q2 report. At this rate, it is projected that Facebook (currently at 7.9%) will surpass Yahoo! (16.8%) and be second to Google (40.1%) for overall video streams by the end of the year.
A prediction many are sure to keep their eyes on.
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[...] you know that 2 billion videos are viewed each month on Facebook? Never underestimate the power of social media. Word of mouth is still the best way to spread information, technology is just [...]