@amleaner, @virtualreality, same with our site. We were on a Close way to out pre-Panda/penguin traffice. On 8/9 march we lost all of the gained traffic to get more worse than july 12 panda update. Since then traffic looks like a rollercoaster. With the lastest changes we saw Amazon, ebay with domain spamming taking over the serps. Nearly no other domain between them.
The annoying Thing about it is, that you are working hard to make a good site for users. And every time you think now you are on the right way. BOOM! It hits you again.
What we did:
-new site structure ( siloing )
-canonical tag for similar widgets
-focus on our niche ( no blabla to any side ) <- and this is the Problem is think, we are to focused/targeted on our niche
-removed/nofollowed external links
-get rid of those soft 404 errors
-reworked every (10.000!) widget with a unique description
-added new pictures to the widgets for more user information
-we got very good stats for user experience/buy experience from other sites
-w3c html validation
-lock googlebot from fetching internal search pages
If i take all this and i do not know anything else we can do ( except to buy links! or link out to Amazon/ebay) I have no clue what the heck g* is looking for.
The now spammy pages that are in serps are all against all rules what MC did say about penguin/panda.