FWIW, I generally find that the majority of referral traffic to the Fogbeam Blog is from Reddit, with Hacker News and/or Twitter next, possibly Slashdot if we got something on there, and then G+ and "everybody else". Until a week or so ago... for the first time, I noticed some posts that we put up where we got more traffic from G+ than from Twitter.
Yeah, it's just one anecdote, and there are all sorts of possible reasons, but it definitely appears that G+ has it's niche in some regards. It might not ever displace Facebook as the main 'generic' social network, but it's no tumbleweed filled wasteland like some people would lead one to believe.