Did Google Penguin hit your website?

[anghel]

Many people have seen their earnings drecrease recently due to Google's Penguin and Panda updates. How are you coping with that? Hmmnnn, I wonder!

[Manov]

Nope, Yet to try........

[mesasa]

One of our site was effected but now again recovering its position back :)

[shakir]

Nothing happened on me but found many webmasters saying it...I think penguin effecting on over optimized sites

[marc1]

yup penguin effect my site very badly. but we recover back soon.

[alemcherry]

Nope, but penguin is a good reminder and warning for everybody. Optimize for users, not bots. Never ever use spammy / black hat techniques.

[bidaddy]

None of the sites I work on professionally were affected but I have seen the effects on other sites I am not affiliated with. Because of the close proximity of a Panda update just a few days before the actual cause and affect is murky at best. Some sites could have been affected by one, the other or both. Additionally, Google has been very active in penalizing link buyers so there's another issue at work which makes a compete diagnosis difficult.

Of the sites where I am reasonably confident that Penguin was the culprit, there is strong evidence of over optimization on the site.

Items I've seen on-site:
Abuse of collapsible divs - way too much content hidden on the page (even if user is able to make visible)
Repetitive keywords in title tags. If the target keyword is used more than twice it becomes higher risk.
Heavy keyword optimization of the meta description - not a positive ranking signal but might be a spam signal
Meta keyword abuse - as description, not a positive ranking signal but may be spam signal
Un-natural on-page text, paragraphs containing a disproportionate number of target keywords. Overly similar heading tags.
Too many pages created only to capture additional traffic by offering slight variations
Links created outside of normal navigation created only to pass anchor text

Many of the sites I've reviewed were guilty of most or all of the above.

Spammy/paid backlinks may be in play with the update as well but since there is a parallel and ongoing campaign to penalize/discourage this practice it it difficult to direct attribute to Penguin.