You have to say, the linear trend doesn’t look good for Dan. Comparing their first few episodes to the most recent ones, the tendency is for shows to add about thirty or forty minutes to their average length (over seventy or eighty episodes). It’s the Freshman 15 of podcasting.
I am sure if you dug into other podcasts you would find similar data. I think there are a couple of reasons for this. First off, as people get more comfortable with each other, it’s easier for them to talk longer and get off track easier. Second, almost no podcasts edit for content, so as the episodes get longer no one makes an effort to trim it down. I have tried to keep our podcasts within the 30-45 minute mark consistently because I know how much it bothers me when podcasts keep getting longer. I only have so many hours in the week and ever-growing podcasts doesn’t help.
(via Marco Arment)