On 2/10/07, Erik Moeller erik@wikimedia.org wrote: [snip]
We've always held that GFDL combined with other pictures and media are "mere aggregations", so it may be in our interest not to advocate a strict interpretation of existing licenses. But it doesn't seem at all unreasonable to me to desire stronger copyleft protection for works which are, in their nature, unlikely to be significantly modified directly.
To be fair, ... we've held that in part because we have depended on it, and because at one time we didn't understand the importance of non-textual illustration as we do today... Not necessarily so much because it made sense or because was good policy. Certainly there are cases where it really is mere aggregation, but by no means are all. In some cases, that the result is a derivative is beneficial under US law at least.
For a long time, enwiki required that all free images uploaded be at least dual licensed with the GFDL, but this requirement was accidentally lost in upload page refactorings more times than I can count... eventually people gave up because figuring out which images were and were not submitted with that requirement became impossible and the lack of a similar requirement on commons made the matter moot. Had I known then what I know now, I would have fought for different requirements. Live and learn.
There have been plenty of cases where I created images while working with a Wikipedia article and enhanced the text of a Wikipedia article around an illustration. The end result being neither the image nor the article could have existed in its final state without the other. This would probably meet the most stringent criteria for a derivative which you could invent. While only minority of our cases are that clear cut, there are many more which could easily be classified as derivative under any one of many sensible definitions such as your semantic relation criteria.