I have manually burned CDs of the music that we have purchased on the iTunes Music Store, but I wanted another backup, so I looked to Backup 3 to do this. Backup has a "QuickPick" that is supposed to allow you to easily backup all purchased music. This doesn't work for me.
I have moved my iTunes Music library out of my home directory. I did this originally when I was using FileVault, as encrypting all of my music took too long. But even though I am not using FileVault, I still like having the music outside of my home directory, as every user on my laptop can access regardless who is logged in.