True, but unless you've added them to a circle they will only see your public posts, and if you never make public posts they won't see anything. In that way it becomes a hybrid of Twitter and Facebook, but it adds a layer of complexity. It requires you to really manage all of your circles, and I wonder if regular users will find that tedious. Facebook and Twitter make it simple, on Facebook everyone you're friends with see you posts. If you don't want someone to see your posts, don't friend them. On Twitter, the whole world can see your posts, so don't post anything you don't want the whole world to see. On Google+ you can do both, or either, and managing that could get really complicated.