Brands and marketers playing in Web video are eager to know what works. The answer from one media buyer is this:  varied creative, linking display ads with video overlays, and interactive ads in the video experience. 

That's what Andy Chapman, leader of The Exchange at media agency Mindshare, told us when we interviewed him at our Beet.TV Online Video Roundtable in New York.

But advertisers still face some big challenges when it comes to online video, he added. "[We need] an understanding and clarity around differentiation," Chapman said. "There are a lot of players and for agencies and clients to sort through all the noise is a challenge for us.  So it's culling through to understand which technology approaches and business models are best."

Agencies too are reorganizing their structures to better understand and act on the growth of digital. This spring, Mindshare, a WPP unit, dissolved its standalone digital unit to integrate digital into the agency's other businesses, including traditional media.

Daisy Whitney, Senior Producer