I like how Google+ managed to take good parts from Twitter and Facebook and use them in this social network. An important thing to know: Google+ is not meant to be an alternative to Facebook or Twitter. It is meant as a centralized way to manage your Google account.
I guess they made a good job with that and they are improving each month. In this free ebook about Google+ written by Maggie Marystone for MakeUseOf you can learn about circles, stream, hangouts, and various tips&tricks.
One of the things I like is that I can insert my frenemies in a circle and then forget about them, since I have only one circle I visit most. From that one I get most of my news and can comment on the posts of tech stars from all around the world.