LAS VEGAS—Are subscription-based mobile content providers on their way out? Panelists at a CES session seem to think so.

“Because of the economy, you will see more and more free ad-supported mobile content,” said Mauro Montanaro, CEO of Fox Mobile Group.

The move will depend on innovative ways of seamlessly integrating advertising and content.

“The sweet spot of mobile advertising is in interaction,” said Brian Johnson, senior vice president of Americas and Asia Pacific for mBlox. “McDonald’s Monopoly this year was a good example of creative interaction. Customers could actually keep track of their boards on their mobiles.”

It’s that kind of unique experience that mobile ad agencies are hoping will bring clients to the medium. Another attractive aspect of mobile ad impressions is they’re still relatively cheap compared to those on the Internet. “The cost per lead can be a tenth of what it costs on the Internet,” said Amy Mischler, vice president of Identity and Brand Services for dotMobi.

But Brian Steel, CEO of VoloMedia, is worried that there’s still a lot of content that goes unsupported. “There were 10 billion podcast downloads in 2008, but very little revenue generated from them,” he said. “We just can’t do that in 2009. That’s just not the world we live in anymore.”