MarcMaronNYerFest_BryanBedder_Getty
Marc Maron was a frequent topic of conversation at the inaugural IAB Podcasting upfront. Here, Maron addresses an audience at the New Yorker Festival in 2014. Bryan Bedder / Getty

Podcasters want to show Madison Avenue they're ready for big ad dollars. At the first-ever podcast upfront in New York Wednesday night, executives and talent from eight of the biggest players in podcasting trotted out numbers about their audiences and treated attendees to brief glimpses at some of their biggest stars, including “WTF” host Marc Maron, tech podcasting trailblazer Leo Laporte and actor Michael Rapaport.

It might not have had the glitz or the sweep of a network television upfront, but it did seem to register with the audience. “It did move the needle for me,” said Ali Din, the chief marketing officer at cloud services firm dinCloud. “From lukewarm to getting pretty warm.”

An "upfront" is industry jargon for a presentation that broadcasters make to advertisers to get their business.

From a raw numbers standpoint, the growth each group pointed to was considerable: Episodes of "Serial," the podcast that tore across pop culture like a comet last year, have now been downloaded 100 million times; Podtrac, the firm that handles ad sales for "Serial" and "This American Life," says its shows are downloaded 60 million times monthly; Play.it, a new podcast network CBS launched less than 10 months ago, has already amassed a monthly user base of 46 million people that listens to nearly 24 million hours of Play.it content every month; Panoply, the podcast platform launched last year by the Slate Group, wound up launching more than twice as many shows as it expected during its first year, thanks to partner demand.

Podcast Listener Stats
After many years of steady growth, one third of all Americans aged 12 or older have listened to a podcast. Edison Research

Not bad, especially when you consider that most podcast listening is still heavily concentrated among iPhone users and that car-based listening, which is seen as a key growth area by some companies, has yet to gather any serious momentum. "It's considerable," Podtrac CEO Mark McCrery told International Business Times, adding that the audience for his company's top shows has grown close to 30 percent in each of the past two years.

Scaling up has meant hoovering up shows and audiences wherever they can find them. Midroll, the home of Marc Maron and, per an announcement Thursday, former ESPN heavyweight Bill Simmons, has more than 200 shows on its roster. ESPN, which announced Thursday that it will be adding an audio tab to its popular mobile app, has a stable of more than 100 shows.

For prospective advertisers, who were told over and over again at Thursday’s event that the power of podcasts is in the power and effectiveness of a host-read advertisement, rather than an automatically generated and delivered advertisement, those network sizes were the only numbers that sounded both good and bad. “That’s a lot of shows to sift through,” Din said.

A Land Rush On Talent

A lot of the programs in these companies’ stables, like “Mike & Mike,” or the Rotowire podcast, are simply lightly edited versions of radio or television broadcasts that companies like ESPN or AdLarge have secured the rights to sell ads against. Another good chunk consists of shows starring seasoned media personalities like Anthony Cumia, formerly of Opie and Anthony, or Taz, a former professional wrestler and experienced television host.

But as these companies continue to scale up, it is creating a growing chunk of shows hosted by very inexperienced personalities that may have built their name doing one thing, but have little experience with podcasting or broadcasting. Julie Lythcott-Haims, the host of a new Panoply podcast about college admissions called “Getting In,” is a former dean of freshmen at Stanford University and has never hosted any kind of radio or media before. The same is true of Elisa Benson, the host of Play.it’s newly unveiled Cosmopolitan podcast, or William C. Rhoden, the former New York Times columnist who began podcasting this summer.

Of course, experience only counts for so much, especially in a nascent medium like this one. Case in point: Elliott Wilson, the journalist and co-founder of the website Rap Radar, has been podcasting for only a month for Play.it. But thanks to a powerhouse presence on social media, Wilson’s “Rap Radar” podcast shot to the top of the iTunes Music Podcast chart in just four weeks.

How this growth spurt affects podcasting as a form and an advertising platform remains to be seen. "We're here because we're responding to market demand," IAB President and CEO Randall Rothenberg told the audience during his opening remarks. "If demand is as significant as we think it could be, we'll continue to grow."

[CORRECTION: An earlier version of this story described Podtrac as the company that distributes This American Life and Serial. It handles those shows' advertising sales.]