I probably won't complain. It's just awkward, and they credited, and in practice I have not set up my website in a way so that I could effectively remove my art from the net again anyway, because I allow robot indexing and archiving, so for example my art is also on the WayBackMachine and so on. So I'm okay with a certain loss of control for exposure.

However, on the bottom of every single page on my website there is already is a big box at the bottom saying that I do not allow distribution without permission of my art. This Tumblr linked to a page with this notice and just ignored it. Fans would not do this to fanfic, and other fans would not consider it okay. I have *seen* the outrage when some hapless newbie fan puts up all their favorite stories onto their own website (all properly credited so no plagiarism). I'd really prefer fandom to be as considerate of artists as of authors and think this Tumblr thing and art reposting through.