http://www.beet.tv/2009/02/industry-standards-set-for-downloadable-media-report.html

While many video publishers distribute their shows as downloadable media, known generically as podcasts and mostly organized via iTunes, there has been scant standardization in advertising format size and measurement. These standards have been finalized, reports Liz Gannes at New TeeVee.
While video streams can be counted, it is very hard to determine the number of subscribers to a podcast who actually watch. In October at our online video roundtable at MSNBC, we spoke about this topic. Mike Hudack of Blip.tv explains how his company is measuring the consumption of downloadble media. Good to see progress is underway.
-- Andy Plesser, Executive Producer