Someone had posted a copyrighted article into the 'wolf' category. I deleted it, please see the discussion at 'WolF'.

For now, I just deleted it by removing all the text, but of course the copyrighted material is still on our server in the revision history. That will go away after 14 days, as I understand it, but I will also try to figure out how to make it go away sooner.

I'm not too worried about this for the future. Legally, it isn't likely to be a huge problem. We just need to instill a very strong social norm on the wikipedia that copyright violations will not be tolerated.