NEW YORK: The Interactive Advertising Bureau (IAB) has announced that it will hold a podcast upfront next month to showcase for advertisers and media buyers the latest developments in podcast programming.

The one-day event is taking place on September 10. "Our aim is to test the market," said Carl Kalapesi, vp/ industry initiatives at IAB.

"What we are really trying to do is educate and showcase great podcasts for marketers," he added. "A lot of folks in this industry have interest but haven't taken the next step."

The interest has been sparked by the unexpected success of last fall's Serial, a spin-off from a radio show where a true story unfolded over 12 episodes. A second series is planned for this fall, with a third in the spring of 2016.

Another factor has been iTunes tweaking its podcast app in September – it offers 285,000 podcasts – helping to attract new subscribers and keep them via navigation.

The result of these two things, according to Hollywood Reporter, has been a 25% increase in the number of Americans listening to at least one podcast in March 2015 compared to a year earlier.

And Matt Turck, chief revenue officer for Panoply, a premium podcast network launched by Slate, told the Wall Street Journal that "we've already booked five times the ad revenue what we sold all of last year".

"Now, that is off of a relatively small base," he admitted. "But there is a great deal of interest among advertisers, and we believe it is going to grow rapidly.

"We just need to come together in a unified front and help show brands how much great content there is out there."

Among those taking part will be AdLarge, Midroll, NPR, Panoply, Podtrac, and WNYC. The inaugural presenters, according to the IAB, are responsible for many of the world's most popular podcasts.

As well as Serial, these include Comedy Bang Bang, Freakonomics Radio, Slate's Political Gabfest, TED Radio Hour and WTF with Marc Maron.

Data sourced from IAB, Wall Street Journal, Hollywood Reporter; additional content by Warc staff