Personally I just have one circle right now made up of work friends. They're all pretty technical; about 60% of them were on both my Facebook and Twitter, and the other 40% were just on Facebook. I was looking forward to using a social tool where I could share and hear more from that other 40%, but they haven't been posting much at all. My reasoning is that if they were big sharers they'd probably already be on Twitter.
My friends who aren't in web or game development have shown no interest in G+ though. I feel like the tool's purpose is to connect with people that I know in real life, so I'm less likely to connect with random but interesting people like on Twitter.
As a result of all this I don't get a lot of updates on G+, and those people who are posting seem to be doing it out of hope that it'll encourage use of the service - they're getting more engagement on Twitter.
Early days and all that jazz, I'm just curious to see if it's taken off for anyone yet.