This is pretty big news: Wikipedia, which has so far been licensed under the GFDL, is moving towards integration with the Creative Commons system. Two days ago, the Wikimedia Foundation requested that the GNU folks modify the GFDL to allow “mass collaborative projects” developed under the GFDL to migrate to the Creative Commons Attribution-Share Alike 3.0 license.
A time of troubles awaits in the near future, when Wikipedians will be asked to decide: relicense the encyclopedia under CC-BY-SA 3.0, or not? Even if the community says no, the new version of the GFDL will allow other content developers to mix material from Wikipedia and CC sources much more easily than was possible before.
(Via Peter Suber.)