I was doing some research and was looking for the University of Minnesota study on atheism from a few years ago as I couldn't find the copy I'd saved. So I ran across an about.com article about it which I thought was pretty slick. But then I saw that the StumbleUpon designation for the article was Pornography! This is nothing new, I had it happen to my That Atheist Bitch (http://thatatheistbitch.blogspot.com/) blog and several of my atheism bits (as well as an article on polyamory and an article on GLBT suicide rates) a while back but I got those corrected with a little help from my friends. There were a bunch of atheist and GLBT articles by a lot of people that got categorized as porn then and this may just be a leftover.
So, if you have a StumbleUpon account, I urge you to go and report the about.com article as NOT pornography here. (http://www.stumbleupon.com/url/atheism.about.com/od/atheistbigotryprejudice/a/AtheitsHated.htm) You can right the report link on the right hand side of the page.
I think they fixed it already. Says it is in the agnostic/atheist category.
Excellent! On the last round, it took a lot longer for the corrections. Thanks to everyone who reported it!