DaniWeb founder Dani Horowitz talks about losing about 50% of their traffic due to Panda.
Video: DaniWeb Speaks out on Recovering from Google Panda
There may be some useful info here. I have been a member there for several years, but have not used the forum for quite a while because the speed performance got to be so bad. She really had the site loaded up with useless garbage and I got tired of waiting 20 or more seconds for each page to load.
I suspect that the speed issue was what got the site wacked, which is in line with Dani's theory that her forum got snagged for something other than Panda.
Dani is pretty geeky, which makes her a little hard to listen to. However, she is pretty knowledgeable about most tech issues.