In a Google Hangout, Webmaster Trends Analyst John Mueller said, in part, in answer to a question about a site that suddenly lost ranking (paraphrase, emphasis added):

"Our algorithms really do try to look out for unique, compelling, high quality content. And if your whole website is built up on essentially providing the same [content] as everywhere else then I don’t know if our algorithms would say this is a really important website that we need to focus on and highlight more in search.

"So with that in mind, if you’re focused on kind of this small amount of content that is the same as everyone else then I would try to find ways to significantly differentiate yourselves to really make it clear that what you have on your website is significantly different than all of those other millions of websites that have kind of the same content.

"But you really need to make sure that what you have on your site is significantly different enough that our algorithms will say well this is what we need to index instead of all of these others..."

The truth of what Mueller says has always been sort of intuitively obvious. But now we seem to be hearing that Google's ranking algorithms are capable of distinguishing content that's sufficiently unique, compelling and high-quality from run-of-the-mill content about the same subject.

If you don't have and/or aren't acting on Jack Trout's wonderful 2008 book Differentiate or Die: Survival in Our era of Killer Competition - get it, read it, act on it before your competitors do.