Re: The point of G+.
Because one day, you're going to type into Google's Search engine "what's for dinner?" And it is going to tell you.
How? Because it knows who your wife is, and it knows your wife's phone number, so it texts her saying "what's for dinner."
Example is crude, I know. But I can't think of a better way to explain what I see Google's end game is with G+.