2012/8/16 Lodewijk lodewijk@effeietsanders.org:
Hi Matthew,
The Russian photo was a copypaste error, I added the link at least similar to the other photos. If any of the other photos miss such a link, that is likely also an error on my side and I'd happily fix that.
Given the arguments you gave, it might indeed make sense to add the CCBYSA link & explicit mention after all. It'll be a tough job but well... it is a fair enough effort to make. This is something that hasn't been done with any of the images yet.
I personally find the Facebook terms on this kind of vague since they don't specify their 'license' very well. According to the Facebook FAQ it would also be allowed to post content when you have permission to post it - which I could claim to have through the CC-BY-SA license. As long as I follow the terms of that license of course (which indeed includes linking and mentioning the license).
In Facebook's terms of use there is a claim that Facebook can sublicence the content, while in CC-BY-SA there is a clause cleary stated that you cannot sublicence the content but only release it under CC-BY-SA or compatible licence. IMHO just because of this reason one cannot upload CC-BY-SA licenced pictures to FB without direct copyright owner's agreement. When uploading antything to Facebook you agree on their terms of use, which means that the content is published under their licence, not CC-BY-SA even if you claim that you release under CC-BY-SA. Moreover - at least in case of our Polish part of WLM regulations we assure uploaders that we will re-use the pictures under CC-BY-SA conditions only.
Of course the owner of the copyright can do whatever he/she wants with their own works as CC-BY-SA is non-exlusive licence. Anyway, I think that danger that any WLM photographer may sue us is close to 0, but there are people who hate FB - so they can make a noise about it in Commons' discussion pages or e-mail lists.