As a fun followup to my previous post, I thought I'd illustrate the same point using this very cool Creative Commons comic. After reading the comic, you should have a clearer idea of what the CC licenses are all about, right? In addition, I like the spectrum perspective shown in the opening and closing panels, as well as the 2nd-to-last panel explaining "Public Domain."
So here are the (rough) analogies I draw:
Copyright => Copyright EULA's
CC:Share-Alike => GPL, EUPL, etc.
Public Domain => LGPL, etc.
As I see it (and maybe Creative Commons sees it...?), Public Domain, and not GPL, is the extreme opposite of Copyright. With that in mind, my order of preference is from most-free to least-free:
1. Public Domain, LGPL, etc.
2. GPL, EUPL, etc.
3. Copyright, Windows Vista License, etc.
I also just read a descriptive scenario whereby new CCPLv3-SA licenses are incapable of ENFORCING their copyleft doctrine down the chain of recipients.
See, if I was Sam, I would just put work A into public domain and stop worrying about it. And if first recipient, Dave, wraps it in TPM, creating d[A], then that's Dave's work now. 2nd-recipient Bob may like d[A] more, but it's up to Dave to give him permission to modify d[A]. Bob can always come get A from me with no strings attached.