While online video is effective in building brand awareness and "upper funnel activity," the big value is as a "vast bed for testing" television advertising, says Donnie Williams, Chief Digital Officer at Horizon Media, the biggest independent media buying shop.

He also speaks about the opportunities and limitations of video ad networks.

Williams will be speaking at the Elevate conference this Tuesday in New York.  Beet.TV is a media sponsor of the event.

Andy Plesser