From the WebProNews article: "Another thing on the quality guidelines list is: “Don’t create multiple pages, subdomains, or domains with substantially duplicate content.”
Of course, like the rest of the guidelines, this is nothing new, but in light of the Penguin update, it seems worth examining the guidelines again, if for no other reason than to provide reminders or educate those who are unfamiliar.
Duplicate content seems like one of those that could get sites into trouble, even when they aren’t intentionally trying to spam Google.
Even Google says in its help center article on the topic, “Mostly, this is not deceptive in origin.”
“However, in some cases, content is deliberately duplicated across domains in an attempt to manipulate search engine rankings or win more traffic,” Google says. “Deceptive practices like this can result in a poor user experience, when a visitor sees substantially the same content repeated within a set of search results.”
Google lists the following as steps you can take to address any duplicate content issues you may have:"
Useful. Important. 8/10
Check them all out in the original article here: http://www.webpronews.com/google-penguin-update-dont-forget-about-duplicate-content-2012-05