I mention it because recently iPods were deemed to be "legal" by USA Track and Field for marathons. So get used to seeing iPod people at races. The wording was clugi at best. All electronics are legal: phones, radios, iPods, Gameboy.
This has to be the single dumbest sports decision I've heard of.
At the California 70.3, I saw five iPods and three mobile phones on the run course. The iPod people were in their own world but studies have shown that music helps athletes stay in rhythm and perceive less pain during exercise. The phones were another matter entirely. All older female users were getting information on their "Kona competition" from different members of their entourage.
I view this as blatantly unfair. If allowed to survive, we'll get what we see in Kona every fall. People on bikes with mobile phones and radios in the lava fields telling racers where they are. I view this as different than a spectator in a static location.
Leave the electronics at home. When you turn pro and race with Lance Armstrong, they will give you a radio.