This makes me think that a particular licence, that explicitly requires an approval of all future licences that unambiguously reduce restrictions imposed by any future licence changes, might be a good idea. (In more sane words: By agreeing, you grant us the right to move your stuff to an even freer set of rules than these ones.)
"You agree to release your work under licence X or future versions of licence X as approved by organisation Y" is pretty common, and hasn't been seriously challenged (even when people whine about it, e.g. Wikipedia using the CC-by-sa provision of GFDL 1.3).
(Turns out that Stallman and Moglen knew what they were doing when they invented copyleft.)
If you've been following the announced partnership between LessWrong and Castify, you'll know that we would like to start offering the promoted posts as a podcast.
So far, everything offered by Castify is authored by Eliezer Yudkowsky who gave permission to have his content used. Because promoted posts can be written by those who haven't explicitly given us permission, we're reluctant to offer them without first working through the licensing issues with the community.
What we propose is that all content on the site be subject to the Creative Commons license which would allow content posted to LessWrong to be used for commercial use as long as the work is given proper attribution.
LessWrong management and Castify want feedback from the community before moving forward. Thoughts?
Edit: EricHerboso was kind enough to start a poll in the comments here.