I love Libsyn. At the beginning of the year I elected to start hosting my own podcast, but prior to that Libsyn hosted every podcast I had produced to date. I still have warm fuzzies for them as they are one of the olderst hosts on the planet and they really, truly get podcasting.
While there were never any restrictions on commercial use of the Libsyn service before, they're going one step farther now and are about to launch Libsyn Pro.
It looks to me that the pro version is designed to be something that a corporation or podcast network can use to manage their cast of shows. Looks like an uber account can set up the main parameters and then individual accounts can manage their own podcasts from that point in.