The blue / light blue / grey colorscheme gives a real Facebook look and feel. Almost the same structure as the Facebook webinterface, really contributes a lot to this feeling.

That's kind of interesting because another comment I saw in Google News said the “defining characteristic” (or something like that) of the application was that it didn't look like Facebook at all. Not being a Facebook user, I can't say which is true, but the divergence of opinion is interesting.

Steve

P.S. I love that last screen shot (lower right). The way the pop-up menu is displayed changes the status from “Jim Wilson is looking forward to drinks with the gals tonight!” to “Jim Wilson is looking for gals tonight!”