I don't think the bubble is bursting at all. If anything its maturing. It's not working for large companies. But I now listen to podcasts more than I read books and I learn more that way as well. Most of these podcasts come from small independent sources. Human conversation was how stories were spread for thousands of years, until the printing press. Now we have the technology to share information through conversation, but with the same reach as written language. Among my group of friends, talking about what podcasts we've read has become very similar to the old conversations we had about boost. The best podcasts are in depth often niche discussions similar to books. The don't require the production level of TV, which is great because a lot of great podcasts don't have a large enough audience to support that cost. They require time, and expertise to produce, not much money.