The thing that killed film cameras is that digital cameras just work better and have at least one killer feature -- Instant review. That is a massive advantage for consumer and professional alike. Once the disadvantages were moore's lawed away -- quality for professionals and price, size and printing for consumers -- film could not stand.
There is no killer feature with download music. I can get it faster, but so what? It might grasp the fashion markets, but not everyone needs music now. It has added no killer feature and it's not even cheaper. And one thing that's not like all the others -- it's a worse product. Most people have a CD player in their house and their car. And their computer. And their friends have CD players †. And they can play their CD's everywhere, and they can rip them and put them on portable devices, and they can display them in their living rooms.
Newspapers - physicality is nice, but I can well see them disappearing, because digital news will be more convenient, cheaper and more up-to-date. The winners will be the digital newspapers that preserve or enhance the paper reading experience, which might not mean having reporters and so on, but will mean selecting and presenting information in a way people value (in particular, mirroring the reader's values. It just occurred to me that the Daily Mirror in the UK is the best (and most ironically) named newspaper ever.)
[1] http://www.prosoundnews.com/blog/30154
† iPod docks in hifis and cars are getting penetration, but are not standard yet, and certainly not ubiquitous. Fixing this will be one thing that kills physical music.