Time is a factor – I think we have (artistic) ideas about when someone else’s work is aged to a point that it’s OK to proudly incorporate it into our own. And, I don’t think licenses themselves are going to immediately change how much we’re out of whack with this–where we have to tend to think that only works from the 100 years ago are OK to use.

Obviously, some individuals and cultures find ways to incorporate works in a very present way – like Hendrix covering “Sgt. Pepper’s . . .” 2 nights after the album came out is a different standard of time than us waiting another 100 years or whatever for that song to be free to remix.

But, I think the real effect of each of the CC licenses won’t be so obvious for another 10-20 years, when there is another generation that has maybe grown up more free to remix / reuse the present and very recent past.

On that note, I’d like a license like CC-BY-SA that automatically turns to something like a CC0 after 4 (or 7) years. I think the original limited duration – aspect of copyright was one of its smartest features, in terms of being non-destructive to the arts.