We could just give them a name other than "Circle", like "Public Topics", "Broadcast Channels", or "Columns". Personally though I don't think it is confusing to have Public and Private circles.
When I publish a post via my +blog, and it's about my piece of software, I want to publish it to my project followers, but I don't necessarily want to target it at my family. Does that mean I want to hide it from my family? Not necessarily.
The need to solve this problem is palpable, although Google is not clear when or how they will address this problem. http://anyasq.com/79-im-a-technical-lead-on-the-google+-team...