MediaPost reports that a new industry trade association, dubbed the Association for Downloadable Media (ADM), has just been formed, with the purpose of developing standards, best practices and audience measurement for ad inclusions in podcasting and other portable audio/video content.

While over 85,000 podcasts are available on iTunes alone, their ad potential has not been fully explored. Tracking has been a major problem, as it is difficult to gauge how many listeners a podcast enjoys when the media can be distributed in multiple ways once downloaded.

The ADM consists of 15 companies, including NPR, Nielsen and Apple. Other businesses seeking to join may do so at www.downloadablemedia.org.

The cost is $1,000 for companies and $150 for industry individuals, including podcasters, video bloggers, producers and distributors. The group is also seeking nominations for board and chair seats.