I think that GNU FDL is perfectly fine for Ultimate Wiktionary and there is no need to change the license. The license is perfectly compatible with the .DICT format, so there should be no problems at all. Thinking about how to import data from wiktionary in the ultimate wiktionary may pose a few puzzles with respect to FDL compliance, but I don't see any significant problems. The import script should keep track of who contributed to a chunk of data and take note of that fact. The history may be a little more problematic, and I think we will want to get advice on exactly how to do it. But changing the license to something else would require throwing away all existing work in wiktionary, which seems quite unwise to me. --Jimbo