I agree with searchrank.
I have just gone through what you and a lot of others are going through at the moment.
This may help you all relax a bit.
I reported about three or four weeks ago that I had "dropped off the face of the earth" with Google. I had completely restructured my site. I began to think it was a stupid thing to do. It turns out it was'nt.
Anyway.......I was advised to sit back and be patient and I found that terribly hard to do being the sort of person I am. BUT I DID!
Low and behold I'm now back in the same positions as before. Better in some cases, slightly less in others, but back on the first page with a HIGHER pagerank!
The sites that came from nowhere to replace me three weeks ago (and IMO were spammy in their structure and LOW in page rank ) have dropped back to where they came from.
Every page in my old site had a rank of 3. My home page now has a rank of 6! Some rank 5 and the one's I need to finish off....... some have PR0.
That tells me Google likes my site and as a result pops back almost daily to visit me and will rank my PR0 pages higher when I sort them out! Believe me I will do!
IMO Google are making sure that these regional sites (mine is one) are relevant for what the searchers are looking for and then sticking the sites which are, back in the results with a better ranking.
This then tells you that Google likes the structure of your site and views your site as quite important.... hence the higher pagerank.
IMO it's telling me I need to sort out the PR0's for those other pages within my site that still need those finishing touches to keep the rank Google thinks you deserve for your efforts.
I would be interested to hear other opinions on this when the pages DO come back up in the SERPS. If they don't, then IMO it's only Googles way of telling you a bit more work is needed.