David Gerard <dgerard <at> gmail.com> writes:
What about extensions? Would they count as derivatives of MediaWiki for license purposes? (I suspect they would, given Automattic regards WordPress themes and plugins as derivatives and requires them to be GPL.)
IANAL, but if there is some flexibility here, I would argue that extensions should *not* be considered derivatives. Legally, because extensions do not contain MediaWiki code (beyond using the programming API provided by core classes); in practice, because we have many extensions licensed under licenses that are incompatible with GPL,[1] and I don't think we should require people to choose a GPL-compatible licence should they want to write MediaWiki extensions.
I think switching to AGPL needs more careful consideration. Not everyone may agree with its philosophy, and it'd probably significantly impact some of the biggest users of MediaWiki (Wikia comes to mind).
wctaiwan
[1] http://www.mediawiki.org/wiki/Category:MIT_licensed_extensions