Steven P. Jobs put his talent as a master salesman to the test when, in 2005, he introduced new Apple software for downloading digital audio shows. The format was so incipient that he struggled to describe it.

“It’s sort of like TiVo, for radio, for your iPod,” he said. “It’s not just the ‘Wayne’s World’ of radio, but real radio is jumping onto this.”

But he was clear about the potential. “It’s getting very, very exciting,” he said.

He was talking about podcasting — radio-style shows made for the Internet that have, in recent years, exploded in popularity. These days, many amateur podcasters are going professional. Major media organizations, searching for answers and bright spots in a fast-changing and confusing digital world, are releasing new shows every week. Advertisers are starting to follow them, and so are millions of dollars of venture capital.

It is, in other words, an industry now, one that Apple essentially gave life to and still dominates. Yet at this moment of triumph for podcasting, concerns are growing in the community about how much Apple actually cares.