If ever there was a next big thing in online advertising, this is it. We've recently helped one of my agency's clients, Travelocity get in on the podcast sponsorship movement, redirecting online ad dollars to this promising alternative channel.

We've been working with Travelocity since 1998, and it's always been a great client. From the beginning, the client has been open to pushing its online advertising into new areas. The explosion of iTunes and podcasts, combined with other advertisers' hesitancy to enter the space, made the timing, relevancy, and potential of doing a podcast sponsorship obvious to Travelocity. So when we suggested a partnership with public television travel guru Rick Steves, it was an opportunity Travelocity couldn't pass up.

Steves is America's leading authority on travel to Europe and beyond. He's done over a hundred PBS travel shows and authored 30 bestselling guidebooks. Currently, he also does a weekly travel show on public radio, "Travel with Rick Steves," which has built up a massive offline following. Now with the popularity of portable devices like iPods, his fans worldwide can listen to the show whenever they want, along with some brief messaging from Travelocity. Truly a match made in travel heaven.

According to a recent PQ Media study, podcast ad spending is projected to grow at an astounding compound annual rate of 154 percent over the next few years, outpacing even other alternative ad options, like blog and RSS (define) advertising. John Keehler, our strategist behind the sponsorship initiative, believes these types of advertising will have significant impact beyond merely generating brand awareness.

"Through sponsors like Travelocity," Keehler said, "big fish and even not-so-big fish podcasters can focus on doing what they do best: providing free, informative, and entertaining content for their listeners. And that benefits everyone."

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