Recent panda attack?

I have been on the edge of my seat the past couple days. All of my sites seemed to be slapped by google. One site that has been #1 strong has been dropping each page by the day. Same for my other front page position sites. Overall, I lost 50% of my traffic. Keep in mind I have doing the usual diverse links and varied keyword anchors no huge blast to money sites.

what is going on?!