Ok, my website was affected from the recent fiasco and my site dropped on average by 5 positions for all pages, i.e. previously #3 for blue widgets now #8.
The only thing I can see that has changed with my website is the number of indexed pages:
-Before Feb. Google had almost 95% of my pages indexed.
-Now Google has less than 60% of my pages indexed.
We are talking about a few thousand pages build over 4-5 years. From Jan. until now I have added no more than 100 new pages. My site is well-structured and every page has at least 2 links going to it so spidering is quite easy. Not to mention SiteMap is full and up to date.
So where did all those previously-indexed pages go? Is it normal for Google to just drop a couple of thousand pages out of the blue?