Wikimedia is migrating all of its GFDL content to the CC-SA license:
Other massively collaborative sites that use the GFDL have only until
August 1 of this year to make a similar license switch, under the
terms of the latest GFDL license.
Other sites and authors that are currently using the GFDL to be
intercompatible with Wikipedia content, should plan to switch to CC-SA
around June 15 (when the WP license switch is scheduled to take
Please share this message widely. The time-constrained part applies
only to other wikis and massively-collaborative sites that chose their
license primarily to maintain WP compatibility.