Audible has introduced the first components of AudibleWordcast, a platform that for now inserts ads into podcasts, audits audiences and offers secured transactions - but will, starting in the first quarter of next year, also enable tracking of ad impressions - reports ClickZ. Audible says that podcasts in its .AA format will allow audio producers to measure both how much of a file and what ads have been played.

"Once you have the ability to test and measure who's listening to what and how much, you're able to build a rate card, and that should be a driver of revenue," David Joseph, VP of communications and strategy for Audible, is quoted as saying.

Podcasters would take care of their own ad sales - Audible does not offer media representation; but Joseph said it would consider doing so.

There are no minimum requirements, and Audible expects a wide range of users, from large media companies to independent producers.

Audible plans to charge podcasters 5 cents per listener download for its expanded service, which includes measurement of usage, and a half cent more per download if the podcaster wants to have Audible insert an ad, writes CNET. Podcasters who want only to measure the number of downloads but not usage would be charged 3 cents per download.