@Shepherd - Yup April 24th was our 1 year anniversary of being hit. We were initial hit and lost 20% of traffic and then a month later another 10%. Since then it has been a slow steady decline to where we have lost just over 50% of traffic when compared to the previous year. We lost some important keywords since our income is down about 75%.
I have tried a number of things and nothing seems to be halting the slow steady slide. We plan on replacing our theme soon with something a little more modern. I hope this helps. Most of my competitors (with quality content) have disappeared as well from the SERPS. If I take the current SERPS in our niche as any indication of what to do I should be creating thin content pages from 3 years ago and applying black hack techniques to improve my ranking :-(