My commute is 9 miles, 3 on MUP, 4 on bike lanes and 2 on neighborhood streets. I listen to an I-pod, but as stated above the volume is at a level that when I'm in traffic I don't hear the music. I also check my mirror often for vehicles and other bike commuters. On the MUP I don't encounter too many other commuters. While doing recreational riding I do not listen to an I-pod, usally a higher number of walkers/bikes around and in a group ride setting.