I've missed one that should be big, but for some reason it doesn't seem to have the cachet of Facebook, Instagram, or Twitter.
I stumbled across an article that talks about how those +1s can be very useful for things like Google search. I won't rehash the article, so make sure to click on the link.
I should go now and update my Google + page...
How about you? Are you on Google +? When was the last time you checked it out?
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