Sure, microphones and book narrators have been around a long time. But with a $60 microphone, a computer, a bit of egg crate foam, an Internet connection, and a glass of water and we can record--and distribute--our audiobooks ourselves.
Maybe in the woods. You know, on your own. Writers often write out their thoughts to understand them better. What if we spoke or...
Audio has been around since, I suppose, the spoken language. The difference now is distribution and availability. Audiobooks, podcasts, smart phones, voice controlled home...
The ultimate in content repurposing.