My impression so far is that the service has some legs to stand on. One of the best features is the use of Circles. It’s like a fine tune control on your posts giving you the ability to determine who sees your posts.
I am using a “training wheels” tool with Google Chrome browser. It is a Chrome extension called Extended Share which lets you share a post from Google+ to Facebook and/or Twitter. So far, I haven’t had any luck with getting posts to Twitter but I have been able to share posts with Facebook.