The edge, for me, is that I actively want to keep FB friends and family only, but would also like a separate public persona. G+ is Twitter for people who don't know that 140 characters is a feature.

That's not really something that helps Google. They want everyone there, not just self-proclaimed 'early adopters.'

This is my experience with it: http://news.ycombinator.com/item?id=3020785

That is only for special lists. When you add someone as family member it gives you the option to add the relationship to your profile.

The other person has to agree to that, being identified as family or a coworker on your profile.

Not being put on a certain list.