Hello,
Photographers (at last in France, I don't know if it is the same in other countries) are facing a serious profesionnal crisis due to several factors, one of them being the massive usage by the media of "Royalty Free" photographs. As several companies built their royalty free photographs databases through photo contests, the "Union des Photographes Professionnels" (an association of pro photographers) has established a blacklist of photo contests where participants abandon their copyright & royalties to the organizers of the contest.
So, as the CC-By-SA used on Commons allows commercial usage, they referenced WLM in this blacklist.
However, this had very little impact : no mentions in the press, very few on Twitter or other social networks. We prepared an answer for them but it is currently awaiting final rereading before sending.
Sylvain.