I love having Spotify, because it means I get to listen to a large range of music I couldn't before...and legally, this has meant my wide taste in music can be pleased and I can listen to what I want based on my moods, however, it is nice to have a physical copy in your hand, but I'd be willing to give that up for a reliable service that's fair and convenient. Though of course, music can still be purchased, I mean as a radio DJ (even for student radio) I can't use Spotify to play music over the air and we must own copies of the music we play. Also, Spotify doesn't work on an iPod classic or traditional MP3 players.

Nor are Spotify's alternatives available. But Spotify and its alternatives I think are a progressive way to get music out to music lovers and cutting down piracy...or so I perceive.
OnLive I'd treat with the same principle, I mean the video shows that, actually, it IS realistic, even based on how unreliable the internet can be, OnLive takes that into account - they go into depth about the algorithm in the video and it has me convinced, and well, the demonstration shows that it works.
For SD, I believe the speed needed is 1.5 megabits per second and 5 megabits per second for HD. For coverage, it would require many OnLive servers, essentially if you're a 1000 miles within distance of one, you can use it. I believe the US is already covered. They have considered the server routes of ISPs and how they might make the distance data traveled longer, but deals with ISPs has solved this issue. Watch the video basically, it has me convinced and it has ISPs AND top game companies convinced too.
Though my main concerns are:
How quickly will servers be spread? (In order to give coverage to more people, like us Brits)
And what are we looking at for cost? I can't imagine the service to be free.
As for death of the CD/DVD, I don't think it necessarily will be, perhaps for PC gaming due to piracy (piracy is kind of ruining PC gaming as it is). But even if it did, I see it as solving more problems than creating.