Wall Street Journal: In the fierce competition for online video ad dollars, YouTube has the upper hand when it comes to extending the shelf life of a marketer’s video, according to a new report. Research from video content advertising firm Visible Measures says brands enjoy a so-called “ripple” effect when they share a new video on YouTube that drives views of the brands’ older videos, an effect that does not happen when they share a new video on Facebook. As a result, videos on YouTube are watched by more people over an extended period of time, the study claims.