Real-time bidding (RTB) for online video is poised to explode over the next 18 months. According to the Forrester Consulting study "Online Video RTB Primed for Dramatic Growth," U.S. online video RTB spending will reach $387 million in 2012 and $667 million in 2013. But what is causing this rapid growth? The surge is primarily due to the success RTB achieved already in display. Those using programmatic buying for display advertising have been among the early adopters of RTB in video. Their familiarity with the technology and audience-based buying has lowered barriers to entry, whi...