Uber_SEO - 9:03 am on Apr 24, 2012 (gmt 0)
I worked on a site that got pounded by Panda. We did everything that we thought could be causing it (including removing the ads). That was about 9 months ago. We've still seen no recovery.
I now don't think Panda has anything to do with what Google said it was about at the time, and I wouldn't remove your ads.