I also listen to them for the music, especially the folk sounding music.
The Brazilian announcers all seem to have those deep, booming voices...
A lot of the time on R. Nacional Da Amazonia they take a lot of phone calls from all over Amazonia, Rondonia, etc.
I've frequently heard the announcer say to people on the other end of the phone line "Que fala?", which roughly seems to mean "what's happening?" (Actually, it's more like "what have you got to say", as 'fala' is Portuguese for 'speak' or 'talk', much like the Spanish "habla").
I don't understand much of the language, but learned Spanish in high school and college and recently got a book on Portuguese to try to decipher a bit more of what I hear on the station, as it comes in so clearly nearly every night.