I seem to remember as show that said if you prefer not to listen to the radio in the car that you are more likely to be anti social and if you always listen to the radio then more likely to be more social.
By that guide, I am more anti social.
I only listen to the radio/ipod when on very long trips. I find the radio slightly annoying and distracting when city driving.
Flying, I love to listen to the hum of my Lycoming, or talk to someone flying with me. Otherwise I prefer to listen to ATC for whatever I might learn or better situation awareness.