[jeffdavis]

I don't think anyone is claiming that the concept of "circles" is a radical innovation. It's quite natural, and similar (if not identical) ideas have been expressed many times before (from what I've heard about "circles" anyway).

What's news is that Google is putting its full weight behind the idea, including a slick implementation. And it might turn out to be a better alternative to Facebook, which would mean a big shift in the markets over the next few years.

[naqabas]

Exactly. Just like this company called Beluga - http://belugapods.com/. They use 'pods' instead of circles.