Someone asked why people would pay for digital music downloads if they could get them for free. Leaving aside the issues of quality and time (ease of location, etc), there's the basic concept of "free". Most people don't like being criminals. There are lots of things one can get for "free" if one is willing to steal them. From salt and pepper shakers at Dennys to music to software ...
The biggest reason people will pay for digital content is because they would rather not resort to being thieves.
As for what price people will be willing to pay, the market will determine that. PressPlay, MusicNet, Rhapsody and now Apple have all set initial pricing where they think it will work. The market then will dictate where it moves from there.
Ironic that buying a record for $10 today is actually less in inflation adjusted dollars than what people paid 25 years ago, yet in a nation filled with a growing sense of entitlement everyone wants everything "cheaper".
I would suggest your son might not be a fully accurate reflection of where the market for music develops in the coming 3-5 years. I assume eventually he'll make friends with someone in a business that relies on intellectual property and come to have a different sense of what's "free" and what's "stealing". I predict there will be a gradual change in behavior. Gradual being the operative word.