FreeGameDev

Maybe this one is more appropriate in terms of detail:
http://opengameart.org/content/future-fighterjet-v2

That model's GPL would influence the source code licensing. http://opengameart.org/content/future-fighterjet by Julius on which it is based is ok (CC-BY-SA). I would argue that a GPL-only relicensing of that model is violating the rights given by Julius CC-BY-SA. [provided they haven't asked for permission before] However it is Julius decision. Maybe they could dual license? The mesh at least?

No, it's not a violation of the license, because Julius' model was only used as a reference, with modeller Origin "rebuilding the model from scratch" i.e. completely recreating it, so Julius's model was not actually used.

Sorry, you're right, it is a rebuild. Places it again into a grey zone: http://forum.freegamedev.net/viewtopic.php?f=51&t=1121 This time with reversed roles...

Hmm, I am actually not sure if it is a total rebuild. But in any case, my mode was dual licensed... the new author just decided to release his changes in a branch only preserving the GPL license, which is ok when you dual license something (dual licensing means AND/OR not AND logically speaking).

But ask him, he might be fine with CC-By-SA also.

Sorry, again, somehow, I overlooked GPL on your model, has to be a case of selective vision and haste. Sure, then they are free to choose of course.