AvantGo/iAnywhere Solutions Crystal King looks at the current podcasting landscape.

Looking out at the podcasting landscape is like doing so from the window of a high-speed bullet train. It's a blur. Once the realm of bloggers turned DJ and talk show hosts, the podcast format is quickly being adopted by media companies and enterprises alike. And where there is amassing interest, advertising tends to follow.

Load up some podcasts into your mobile device and the evidence is clear. Gatorade sponsored the Endurance Sports podcast. Durex sponsored the Dawn & Drew Show (conveniently avoiding FCC decency regulations). Best Buy has spots on the top-ranking Engadget podcast. Volvo has sponsored the Autoblog podcast for most of this year. Expedia, General Motors, Proctor & Gamble and Warner Brothers also sponsor various podcasts -- and the list just continues to grow.

The Diffusion Group, a consumer technology research group, recently reported that the number of podcast users in the United States this year is expected to reach 4.5 million, and that the number is expected to reach 60 million by 2010. Sounds impressive, right?

Podcast Alley currently lists 6,304 podcasts available for download. Newcomer Odeo lists around 4,300 in a search on their site. And the 'big daddy' of the podcast world right now, iTunes, lists thousands more. That's a lot of podcasts offered and the numbers just continue to grow. Granted, eventually the 20/80 rule will most likely end up applying -- 20 percent of the shows will carry 80 percent of the listeners.  But is the reach really there for advertisers?

In a July InfoTalk podcast interview on Podtech.net, Forrester's Charlene Li said that only 5 percent of households read blogs, a smaller number read RSS feeds and an even smaller number listen to podcasts. Truthfully, the numbers just aren't there yet -- and what numbers are available don't seem to match up. In March, Forrester released a much more conservative estimate about how many users they expect to synchronize podcasts to their MP3 players -- only 12.6 million by 2010, which is a far cry from the Diffusion Group estimates of 60 million. 12.6 million is a lot of people, but not if it takes the industry another five years to reach that number and not if the numbers are spread out over thousands of podcasts. 

Engadget, one of the top podcasts on iTunes and Odeo, boasts 150,000 downloads per weekly show. The problem, says Shawn Gold, publisher of Weblogs, Inc., a weblog network that includes Engadget, is measurability. "We can track podcasts by the number of server-side downloads. This means that the advertiser needs to trust the publisher that they are providing the correct number of downloads.  It's very measurable when it comes to how many people download the podcast but we can't tell how many people listen to it -- or how many times they listen to it. "

That means users can download the podcast but never transfer it to their MP3 player; or if they do, they may never end up listening to it and instead just delete it later. With current technology, it's impossible to determine what the true reach of podcast advertising actually is. That means there could be 100,000 listeners of the Engadget podcast, or maybe only 50,000, or even less. There is no way to tell.

But even if a full 150,000 people listened per week (and remember, we're talking about one of the top podcasts), it's still a far cry from the 4.6 million readers per month that check out the Engadget website. When you look at it in those terms, it simply becomes a matter of reach.

Jason Calacanis, chairman of Weblogs, Inc., recently stated on his personal blog:  "Volvo and Best Buy are our sponsors right now, and it's a fun business … but I just don't know how it scales. I mean, can we get to one million people listening to a podcast? I'm not convinced that there will be many of these …"

Because of this challenge, Weblogs includes podcast advertising (often called "podvertising") as part of its overall package. "150,000 downloads is still limited reach so we package podcast advertising with branding on the web page," said Gold. "It's about innovating and communicating with the audience. By credibly inserting themselves in the podcasts it becomes a value-add in a total communications package for blog advertisers. "

So if the reach isn't there, what is the allure for companies to advertise in podcasts? It's the type of audience -- technology savvy trendsetters. While there are millions of MP3 players out there, podcast listeners are still a relatively small group. Right now, the people listening to podcasts are consumers who get excited about next-generation technology. They are music and technology enthusiasts. They tend to be affluent and educated. And advertisers see them as excellent forecasters for what will be hot -- and, ultimately, as key influencers on other people. 

In addition to reaching trendsetters, advertisers see the potential for touching a very targeted audience through podcasts. A company selling golf clubs may not have much traction on a podcast about cats. Likewise, an electronics retailer might not find the best audience on a podcast about weight loss. However, Best Buy's sponsorship of the Engadget podcast gives them an edge because they are tapping in to their core consumer base -- a trendsetting audience that is very excited about the latest electronics.

The Greater Miami Convention and Visitors Bureau (GMCVB) was looking for a way to promote the growing culinary tourism in the area. They turned to the popular Grape Radio podcast to reach a highly targeted niche audience of food and wine lovers. Miami is home to several food festivals including one of the largest in the country, Miami Spice Restaurant Month. "This year's sponsor of the festival is Campo Viejo Wines," said Rolando Aedo, GMCVB VP, marketing and tourism. "This is our first foray into podcasting but with Miami Spice this summer, the timing was right. Demographically Grape Radio is a great fit."

GMCVB is pleased with the buzz generated so far. "Because podcasting is still in its infancy, it's not as though we're looking to generate 'x' amount of clickthroughs," explained Aedo. "We're positioning our brand and generating incremental awareness."

The GMCVB is also looking into creating their own podcasts, which they will use as a vehicle to bring greater depth to the information on their website. Aedo said they would advertise the availability of the podcast via more traditional means, on the web and potentially in print. It's an interesting evolving trend -- the podcast advertiser becoming the podcaster. Last fall, Adam Curry, the father of podcasting, approached Heineken to advertise on the Rock & Roll Geek Show (now sponsored by Rykodisc). Instead, Heineken decided to create their own podcast featuring the latest in music interviews, news and concert information.  It's not surprising-advertising on a podcast can cost a lot of money -- creating your own costs little and the branding potential is far higher with your own webcast than it is with 30 seconds of advertising on someone else's.

There are certainly reasons for advertisers to be cautious about podvertising: the market is still nascent; technology to track advertising on podcasts isn't yet available; and the reach is barely a fraction of what other advertising venues can bring. But advertisers shouldn't rule it out -- finding the podcast with the right mix of trendsetting listeners may prove to be a rich goldmine. As technology improves, podvertising may turn out to be the next best thing to radio and as such, could be a tremendously valuable advertising venue. For now -- we'll just have to wait and see. Or better yet, listen.