Baran, head of new media advertising at Channel 4, warned publishers that they should only get involved in online video if they're in for the long haul.
He said: "It's a very young marketplace -- there is not much money there at the moment. If your game is a long-term one, then yes get involved. But if you have short term goals, investing will not be worth it because you won't get the returns."
Another panellist, Geoff Inns, UK product director of CBS Interactive, said that video was just starting to come of age commercially.
Inns said: "The methods for making video a commercial success are not clear-cut yet. We need to keep pushing the boundaries."
Online video deepens the user experience with a publisher's website and increases users' dwell time, which adds value for advertisers, InSkin Media CEO Hugo Drayton told the audience.
But Peter Bale, executive producer of MSN UK, said that it was important to improve the current online ad formats.
He said: "Advertisers and content producers need to work together to create the right ad format. It is not solely the advertiser's responsibility."
Bale was keen to stress that publishers need to create video content that falls in line with their brand's storytelling principles. He said otherwise the video that is produced "looks clunky".
"We all have the right to experiment in this area. We cannot just repeat the passive TV model online," Bale added.
Mark Browning, commercial director at ITN On, noted two key opportunities in online video. He said that the first is branded content and the second is regional and very local video production. "Local town and regional video is providing publishers with new revenue streams," Browning said.
Claude London, director of global web properties at BBC Worldwide, said there will be two types of players in the online video world in the future -- "one will be a scale player, producing large volumes", and the other will be a smaller player "creating more premium content".
Other coverage from today's summit