I have been trying to look at all the sites that dropped in the SERPs but have not been able to find a common problem....I am now starting to think it is related to off-page elements.The one I find really interesting (relevant maybe?) is the results for Google Directory. Before the update they ranked #6 for one of my search terms ... after the update #103. The page is keyword rich, authoritive, and has PR-5. Yet the large drop.Is it possible Google devalued DIRECTORY links?Interesting question. My results are so mixed up at the datacenters I can't see any trend, however, the result that shows up more than anything for many of my keywords is a link for my site at the zeal.com directory.