Not a pro myself, but anyway.

I guess it depends on where you make most money. If you're expecting to make most of your money by selling CDs, then people downloading or copying them is a major problem for you. But if you're expecting to make most of your money from people coming to your gigs, then the CDs are basically a loss-leader. You can afford to let people copy them, because you'll hopefully make up any possible losses by getting a larger fanbase and more gig revenue (and other merchandising at the gigs). Also consider that unless you've self-published, most of the CD price won't be going to you anyway!

But that's your choice for whichever way you want to go - whichever way you think will get you the most income. And in particular, if you're a songwriter who doesn't perform, you're only going to make money when other people perform or sell your songs, so people making copies of their CDs will directly affect your takings.

Incidentally, I do see a big difference between "sharing" as in people swapping CDs with their friends, or even copying friends' CDs, and "sharing" as in some Russian server holding a million different ripped songs for download by the world.

Graham.