CDs, like cheques, still have their uses, and not everyone likes mp3 downloads or using PayPal (for example). I sell many DVDs and CDs over the net - and buy books from s/h booksellers who prefer payment by cheque. Whether it's a generational thing or not, I couldn't say. When it's possible to buy a second-hand, out-of-print book and pop it onto a Kindle or an iPad, I might invest in that technology - but not just yet.

Vinyl was supposed to be dead, but albums are still bring produced on it, and there's quite a cult following for the medium. :-)