Second hand iTunes songs anyone??

Once digital formats are fully protected, there will be no second hand anything. Microsoft already seem to be heading that way with games, so only the original owner can use them. Digital watermarking will probably soon be rolled out to music, giving the pricing monopoly and power back to the labels. It's all about control of the market and the bottom line.

Re. the used media. I've no idea how the pricing of that would work. How would the used price be calculated? Would it be any less than the original and what about subsequent resales?

People would just buy the digital files and create their own discs or complete HDD libraries to listen to offline, much the same as CD purchasers buy CDs rip them and sell them on.

Bizarre.