[neolog]

That was Google+

[chrismorgan]

And they even called it circles.

[mszcz]

...and it was an awesome idea.

The execution and shoving it down users throats, not so much.

[galaxyLogic]

They had circles but I think all the circles were basically equal conceptually, just different people in them (?)

What is needed is built-in support for the idea of "INNER CIRCLE". Those are the people with whom you are willing to share your phone-number with etc.