In 2007 and i would argue before that, live media encoding for streams was pretty much a solved problem but it was often very expensive, and out of reach of radio stations and the information wasn't readily accessible so you could potentially end up giving Microsoft or Real networks lots of money.

I was working on streaming in the late 90s - that was real wild west, had to write solutions myself, and it felt very duck taped together. Luckily it was an offshoot of a largish ISP so we had bandwidth and a lot of servers. incoming streams often used bonded ISDN lines.