SAN FRANCISCO -- It was expected. Someone in the audience at the final ad:tech San Francisco MobileMix session had to ask that dreaded question: "Everyone has been saying this is the year of mobile for five years. Is it?"

Nothing better to get a panel of senior executives from Hearst, Yahoo, NeuStar, Millennial Media, AdMob and iLoop Mobile more energized. They are pros at handling such questions, although it can get tiresome to constantly be on the defensive.

"It's a simple matter of education," said Tony Nethercutt, vice president of sales at AdMob, told agency, brand and interactive technology executives sitting through the "Future of Mobile" session April 21 at MobileMix.

People are looking to their agencies for help with mobile, Mr. Nethercutt said. Hence, it was important for agencies to skill up to better inform their clients on mobile's here-and-now potential.

Michael Becker, executive vice president of business development at iLoop, made an interesting point that illustrates mobile's strengths as well as complexity.

"Mobile's not one channel -- it's eight," he said.

Indeed, it is, if marketers count Web, text, voice, games, video, shopping, search and camera as the channels available on smartphones.

Part of the answer is to understand the adoption curve with mobile.

"The industry's going up and up in the last six months," Mr. Becker said.

Mr. Becker's observations led to Yahoo vice president of mobile advertising David Katz chiming in.

"There are eight different tactics you have to do when you do mobile," Mr. Katz said.

Brands already buying in
The Yahoo executive cited his company's recent work for Porsche as an example of tending to the client's needs with mobile advertising designed to engender brand interest in a luxury vehicle.

All told, more than 100 brands have advertised with Yahoo Mobile with campaigns that belie the notion that mobile lacks the sophistication of the wired Web.

Other panelists also mentioned mobile ads and sites from mainstream brands that are increasingly sophisticated in delivery and objective: work for Fox, "The Fast and Furious" movie with a banner linking to landing page and the mobile site and marketing for the Obama presidential campaign.

Millennial Media vice president of ad sales Marcus Startzel highlighted the targeting capabilities that his ad network used for serving relevant ads to horror-movie enthusiasts.

Another point that the panelists raised is mobile's role in giving legs to other channels such as radio, television, print, outdoor, retail and interactive.

"The mobile focus is becoming an enabling utility," iLoop's Mr. Becker said.

Mr. Becker cited shared mail giant Money Mailer's new emphasis of placing keyword calls to action and short codes on inserts it runs for clients nationwide. That is what he calls mobile-enhancing.

Economy slowed momentum?
That said, Matthew Valleskey, head of marketing communications for mobile services at NeuStar, understood the point of the questioner's doubts on whether the promise of mobile marketing was live.

"Mobile marketing has gotten more sophisticated and then the economy crashed," Mr. Valleskey said.

Such unfortunate timing means that budgets that ordinarily would have gone to newer channels or experiments were cut or scaled back. Mobile may have suffered some of the cost-cutting in overall advertising and marketing budgets.

"A lot of it has to do with the fact that people are not spending," Mr. Valleskey said. "The ROI is there."

But Mr. Valleskey does see positive signs of marketers restoring some mobile budgets.

The Apple iPhone is a key reason for optimism, he said. Not only did it create the knowledge to make creative applications -- to the point of almost 27,000 live in the iTunes App Store -- but it also taught people to be more creative and engaged on the mobile phone.

Those two reasons are positives for mobile advertising and content.

While the panel focused on swathes of the mobile marketing landscape, SMS, mobile Web and mobile banner ads seemed to dominate the discussion.

Not surprisingly, an audience member raised the issue of mobile widgets. Sophia Stuart, executive director of mobile at Hearst Magazines Digital Media and a veteran mobile publisher, took that question.

Ms. Stuart's answer simply reinforced the pivotal role that search now plays on mobile discovery -- a mirror of what's happening on the wired Web.

Ninety percent of people start queries on the Web, she said. So Hearst's emphasis has been heavily on mobile sites.

"Google can't spider apps," Ms. Stuart said.