on topic...
Yesterday I was driving down the street with my (non-runner) girlfriend and a guy was running the opposite way down the middle of our residential street. She started to say what a jerk he was until I told her how it is far, far safer to run down the middle of the street than on sidewalks, particularly at dusk or night. Reaction time is much greater, people just aren't conditioned to look at the crosswalks when at intersections and, especially, do not look at the sidewalks when pulling out of driveways. Not to mention, asphalt is much more forgiving on joints and legs than concrete.
I've never run with an iPod/walkman/etc but I suppose if you have to do it you'd better be damned sure your head is on a swivel. Personally, I have enough trouble "zoning out" during my runs as it is, I couldn't imagine another layer of distraction between me and (potential) death/dismemberment.