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Smart play by Google with G+. They can't just make a copy of FB as nobody would stick around too long. They had to deliver some real advantage and they did (so far). I like the "Circles" idea as I can finally decide whom I want to share my updates with. Opportunity comes from innovation and G+ is taking advantage of it. Now, let's hope G doesn't stop here... and watch out for FB coming out with the "Ellipses" idea...
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