My choice us iTunes overall. But this subject of ownship and transferability was covered in depth in the Wall Street Journal's Mossberg column a few weeks ago. Check:
http://ptech.wsj.com/
It may be under Mossberg File.
I've downloaded music from Napster and Sony Connect (I have a Sony mp3 player). I recently had a hard drive crash, and lost several songs I had downloaded from these services. Sony is a drag in a lot of ways but they allow you to easily download already purchased tracks to a computer or device that you have registered with them, all you have to do is log in. Napster requires that Windows Media Player (and I think it has to be WMP 10) somehow verifies that you own the license, I never figured out how that worked, particularly since WMP was lost like everything else. In any case you'd be wise to back up all your music to CD/DVD (in compressed form like mp3 or wma) or an extra hard drive or both.
The tracks are downloaded to the hard drive (or ripped to the hard drive). The typical usage of iPod has the user "sync" their iPod to the computer, which will update the tracks and playlists on the iPod based on your setting from the iTunes applications.
Do you back up all your music files?
Anything I've gotten from the iTunes store (typically through free credits from the Pepsi promotions), I back up to physical media. I do find the fact that you can't re-download from iTunes an annoyance -- if they have a record that your account purchased a particular track or album, your account should be able to download it multiple times.
Yes, I download music files to my computer's hard drive from the iTunes music store. I also ripped all the songs from the CDs I own (but I never borrowed CDs from others for this purpose). You can select which ones go onto your iPod by simply removing the checkmark in iTunes. Typically, I might keep only 3 or 4 songs from a CD for my iPod.
Anyways, you come home some night and someone broke into your house and your computer is gone. If you didn't back up those music files somewhere, will the music download sites let you download those songs again if you tell them about the break in? If you loaded songs directly onto your iPod and it gets stolen, or you lose it, you are not getting them back, right, or does one continually back up the files stored on their iPod too?
You will NOT be able to re-download your purchased songs if somebody broke into your house and stole your computer. I might add that if somebody broke into your house and stole your CDs, you wouldn't be able to waltz into your local record store and get free replacement either! So it is incumbent upon you to back up what you by. I keep my purchased songs in four different places. My main computer, my iPod, on my laptop and on CD backups that I keep in a safe place. I still have my original CDs so I can always restore those if I had to. Eventually, I am going to get an external hard drive and maintain a mirror image of my music database on backup.
Do you back up all your music files?
Absolutely.