IanTurner - 11:06 am on Oct 11, 2012 (gmt 0)
@radix - your issue sounds like EMD & Penguin rather than a Panda issue.
This thread really discusses this in detail
But I think you will find that because your sites are small and highly focussed they will attract very tightly focussed anchor text for the backlinks, which will trigger over-optimisation demotions.
Check the last page or two of the SERPs for your keywords - go to the second page of the SERPs and then set the &start=nn parameter to &start=950 or 990 to get to the last page.