Hoping to find others who were seriously hurt by Allegra immediately after that update. We've corrected some robots.txt and 301 redirection problems that might have been the cause but no effect. Google has been somewhat responsive and insisted we have no penalty. Our site is MUCH better than when we had much higher traffic from Google. Other experiences?
We were #1 in our category for 16 month, since Google controls the SERPS and we where hardest hit this time around for commercial categories! I believe that Google is filtering sites, or keying on sites that were ranking on the top through search terms containing specific or money keywords or called commercial keywords. In our Industry such words like motorsports or aftermarket hit us hard, after testing with strings of keywords from 2 to 18 and with our complete title we where in the SERPS only after the 18 th keyword we were in 35th place.