The thing that I've always been slightly frustrated with was that the idea of a CD is kind of confined to a material possession that you can put on a shelf. And the idea of music for me is always about both the communication and the sharing of content. And so the interactive part is missing.
When I was little my mom tells me I used to say things like 'Mom do you hear the string section? Do you hear the string section?' And she would look at me and say 'No honey I don't know what you're talking about.'