Never CDs... well, to rip the music from, or burn the music to, but never for listening.
When I'm home that I use the computer (if I'm given a CD to listen to, I rip the music then listen, rather than listen to the CD first), and when I'm not I use my MP3 player.
I wonder if they'll ever create something to load onto your MP3 player besides a CD.
For example:
You buy a cd
Bring it home, rip to computer
If you have mp3 player, then you transfer the songs
If you have an ipod you have to load them into the library
then transfer the songs.
INSTEAD
They should, sell like USB drives, that only have approx. 20-50 MB on them, but they're the CD, and you just plug that into your ipod/mp3 player, or even your computer...
This won't work because it is many magnitudes cheaper to factory press a CD than manufacture USB flash drives.
Why do you even need a USB? They could just have plug in stations at stores, etc. There'd have to be an archive of what you've bought in case you lost the mp3s though. Or you'd have to keep receipts or something.