There were a lot of insightful comments when it was first discussed 8 months ago : http://news.ycombinator.com/item?id=1867807 http://news.ycombinator.com/item?

There were a lot of insightful comments when it was first discussed 8 months ago : http://news.ycombinator.com/item?id=1867807 http://news.ycombinator.com/item?id=1867807 Some more context: Paul Adams, the author of these slides, was Google's social research lead in the UX team at the time. According to Dhanji R. Prasanna, who worked on Google Wave and Google+, Google feared that Facebook might see the slides and copy the Circles idea ( http://rethrick.com/#google-plus http://rethrick.com/#google-plus ): I asked the obvious question--"While I agree that Circles is a very compelling feature, this slide deck is public. Surely someone at facebook has seen it, and it won't take them long to copy it?" I was met with a sheepish, if honest look of resignation. They knew the danger of this, but were counting on the fact that facebook wouldn't be able to change something so core to their product, at least not by the time Emerald Sea got to market. [...] Many were visibly unhappy with his slide deck having been published for all to see (soon to be released as a book). I even heard a rumor that there was an attempt to stop or delay the book's publication. The fear only increased when Paul Adams left for Facebook in December 2010 ( http://techcrunch.com/2010/12/20/paul-adams-googler-whose-presentation-foretold-facebook-groups-heads-to-facebook/ http://techcrunch.com/2010/12/20/paul-adams-googler-whose-pr... ). Happily for Google, Facebook's response, "Facebook Groups", missed the point. Google predicted correctly that Facebook wouldn't be able to change something so core to their product.