Toby Bartels wrote:
The Creative Commons SA licence, in contrast, has no such problems. It is by any objective measure the superior licence; however, we really should license Wikibooks disjunctively with the GNU FDL, so that books can borrow the substantial material from Wikipedia if useful.
I don't think disjunctive licensing solves the license incompatibility issues. We'll be taking content from Wikipedia (GNU FDL) and then offering it under *either* GNU FDL or CC-SA. Suppose someone tries to re-use the content under CC-SA rather than GNU FDL, how does that not violate the provisions of use for the solely-FDL content?
Maybe this will work, though, but we need to think hard about the details.
If we were starting wikipedia from scratch today, I would prefer to create a wikipedia license that says "You can redistribute this content under GNU FDL, CC-SA, or additional free licenses that may be specified from time to time on this page."
But isn't it too late for that?