It doesn’t matter how long we’ve used something; all that matters is how awesome the thing replacing it is. MP3s and automobiles happen to be really, really awesome, whereas ebooks—at least so far—are fairly limited in their awesomeness.
I sampled a bit of stuff from my dad's collection. He has probably a bigger record collection than I do. I try to buy as much as possible, because I've never been able to keep an MP3 collection organized. I like to keep my computers as clean as possible.
I think mp3s are great if you are unknown and trying to get started. It's a good way to get your music out and about. But for those who are established, it's not good at all.
People want to buy mp3s but can't? Piracy ensues. Then Apple strong-arms the music studios into the iTunes store and music piracy drops somewhat. The same, I believe, is also happening with ebooks.
An mp3 is a compressed form of data. It's not the full spectrum. It's never going to sound as good as a record.
