I think that some GNU-advocates would recommend that you refuse the permission they ask for, and instead tell them to license it under the FDL, in order to increase the net amount of GNU-yumminess in the world. As for me, it would depend on the context and so on as to whether I would want to do that.
Thanks Jimmy. I don't think I'm going to insist that they release it under GFDL. The main reason is that the document (not the Wikipedia article) contains copyrighted images owned by Cessna and Jane's, and one nice thing about OpenCourseWare is that they do all the running around to get permission to use those.
moink