Google is actively, maybe even heavily, pushing Google Plus. My Google Plus account was already connected to my Blogger, but recently Google started pushing the use of Google+ for Blogger and somehow I was auto posting to my Google Plus stream. I hate this, this is exactly the reason I left Facebook. Every time they introduce a new feature it is enabled by default. My thought was that Google was not doing that and that they were asking you to use these new features which may be privacy concerned.
Google is doing more and more to push the Plus on you. What about saying in a search result that a topic is heavily discussed on Google Plus? What about using your Google Plus profile for YouTube? And there are more examples.
Is Google doing this because Google Plus is doing so good, or because it is not used enough? Why not let people make there own choice in using and or enabling features. I think it is about time to open up the Google Plus API because right know it is feeling more and more like a closed garden.