This is exciting and all -- and much as I would love to see a serious competitor to Facebook, I still don't know how I would convince any of my non-techie friends that they should switch to this. Circles? Actually I think that many people like the idea of their posts are being read by as many people as possible and not just the ones with similar interests. Although it looks like a big discussion group, the news feed…
on the + side (hah! get it??), the ui looks nice, so hopefully this means google with start paying more attention to the look and feel of their applications.