I have to agree with the following:
>What is very, very weird is, that we have so many good positions back but it seems no one searches for them<
Even WMT shows we are getting 3x the impressions from last week and about 2.5x the clicks, but I can't see where?
A quick update on our experience with "Panda-gray". Almost all of our ranking upgrades have held and still rising. One day words a,b,c will go up, the next day d,e,f will go up while the others take a rest, then back to a,b,c the next day. In a few cases we are back up to over where we were Feb 2011, most not. We don't dare make any unnecessary changes until things stabilize. Those words that dropped back 5-10 positions in the last few days did so for a day or two and then sprang back up 10-15 positions.
>Matt Cutts said that the new Panda would look for "additional signals of quality" that would soften the effects of Panda.
Any ideas on what those additional signals might have been? <
We discussed it in the office and in our humble opinion the top 4 ranking signals they added:
4. The number of DMCA/scraper reports you've filed with G in the last year.
3. If after 2 years of being Pandalized you haven't given up and are still banging your head on the keyboard and renewing your domain, you MUST be for real.
2. Whether you still rank highly on B/Y, as they finally realized who has the overall better results.
1. Whether Page, Brin or Cutts have pinned a humorous cat/dog/squirrel photo from your site to their personal Pinterest boards.
Don't ask me for "evidence" for our guesses. THERE IS NONE. It is meant to be FUNNY (mostly).