I don't understand the comments about file compatibility problems with non-apple products - it seems to me the problems come with Apple products - in that they can ONLY use itunes. In that sense, the Ipod isn't really an mp3 player - it's an mp4 player, because that's the format that Apple (and only Apple) uses.

So if you want to buy music from itunes, yes, you need an Ipod - and if you have an Ipod, you are limited to itunes. But I tend to fill my mp3 player with music from CD's I already own rather than downloaded. If I want to download something, I use Napster, which has pretty similar prices to itunes - non-Apple users can also buy downloads from Rhapsody, Yahoo Music, and other services.

I have owned a Creative Labs Nomad, and now a Samsung YP-T7JX. Both are flash units, smaller than ipods, with FM tuners. I didn't get an ipod because I wanted an FM tuner - when I'm running in the morning or evening I like to listen to the news on NPR. Also, I prefer having a less expensive unit because not only am I prone to losing things, but also to getting caught in the rain while running - it was a sudden downpour that finally did in my Nomad. The Nomad had a pretty bare-bones screen (they are fancier now), but I liked that I could pop out the flash unit and plug it directly into my usb port to add music - no extra cords. What with the digital camera, pda, digital voice recorder, and now mp3 player, tiny usb cords are the bane of my existence.

My Samsung doesn't have a big memory compared to an Ipod - 512 MB, or about 8 cd's - but I don't really care because it's so easy to add and remove music files (I just drag and drop). But now, a year later, Samsung has some 2 gig units that are still a lot cheaper than a comparable ipod.

My Samsung has some awesome features, including the ability to record FM radio (I often use it to record an NPR show and then listen later), and to do line-in recording from a laptop or microphone. However, I didn't find out until after I got it (as a gift) that it isn't supported by Audible.com, so I can't use that service anymore - which is a bummer.

My mom had a Rio, and recently switched to an Ipod - she doesn't have the natural tech savvy of my generation, and she was too confused by the file sorting and so forth on a unit with just a one-line screen. She finds Apple and Itunes more user-friendly.