I'll be checking out your site! thanks!
I too was hit very hard by Penguin. I'm still not sure why, and actually, that's the main reason I am now here. I have noticed, at least in my niche, that the big names moved closer to the top of page 1 in Google, which pushed me down!
The big company I compete with has domain authority much higher than mine, they have millions of incoming links, and that's because they're a huge company! I do think the little guy got hurt most, no doubt in my mind.
But I can't change this, so it's best to focus on those things we have control over, and Georg, I think you have mentioned the most important issues. I have been reviewing all my backlinks, and I just discovered that one Site links to m 690 times, yet to only 28 pages.
I'm thinking that 'looks' like spam. So I investigated further, and the topics of the pages linking to me did not add one bit of value and were not relevant in the least. I hate to get rid of 690 backlinks, but I think they are hurting me more than helping me.