Yes, it's one of many, and the first one to really make sense. Podcasts are already run on open standards (RSS), and podcasters typically have to reach scale before advertisers are willing to pay them... Lightning lets them earn from day one directly from their biggest fans. Podcasting also has no social element (native comments/feedback), and that's something Lightning enables too.

And to echo @k00b, there is a lot of space for experimenting with different ways to move money between creators and consumers on the internet.