I'm not convinced that podcasting has much of a business future. I certainly don't see it as a major threat to radio (satellite radio, however, may someday deliver the death blow.) I tend to think podcasting's future is more likely to be as a form of personal communication, which puts me in about the same camp as Rex of Rexblog. At the same time, I've been adamant when speaking with journalism students, insisting that they master this new medium as soon as possible. (Students -- especially broadcast communications students -- who can't do podcasts are one of my new pet peeves. I have the same blood-boiling reaction to people who don't write but say they have "always wanted to be a writer." Or to students who say they want to be journalists, but don't blog, work for ohmynews or participate in other citizen journalism ventures.)
I'm a little less adamant about podcasting when speaking with B2B publishers...but perhaps restraint is not appropriate.
I've noted an ever-growing number of business-related podcasts. Someone seems to think there is a market here. And even if podcasts cannot be a revenue driver for a B2B publication, podcasts may be another way to expand the brand, serve customers and add to news-gathering capabilities.