GifAnimator - 12:12 pm on Jul 5, 2013 (gmt 0)
I have approximately 2000 people who have me in their circle and have been with g+ for about two years but over this time I have seen my website gradually dropping down in the SERPís.
It will give you a better CTR by having the rich snippet in place on search but I have seen no indication that it helps in any other way.
In my opinion G+ has been set up to get as much information on you to be able to present relevant advertisements when you browse the internet.
This just my two pennyworth, I will point out that I use G+ to interact and have some fun. Many people here have not got the time or inclination to do such things.