I just tried it out last week, with my new-to-me (latest generation) iPod Nano. Music is the best cycling accessory ever.

I was planning on only using it while doing laps in the local parks but the ipod earphones don't cancel noise at all so it does not stop you from hearing that city bus 3 feet off your wheel. I couldn't get the ****ty ipod earphones to stay in but I got these little around-the ear plastic thingies that attach to the earphones which should do the job. I ordered a pair of apple earphones with the remote so I won't have to reach in my pocket to adjust volume or skip songs anymore. Splendid.