The Strangely Compelling Game Mechanic Powering Google+

While "juicy" interface elements are certainly found in games, the "+1" pop-up circle is no more a game mechanic than a text input box is.<p>(I realize I'm being pedantic. As a game developer, this sort of playing fast-and-loose with words annoys me in the same way people talking about "programming in HTML" may annoy you.)<p>Regardless, while I think it overstates the case a bit, I do think that that pop-up is actually a good driver of user behavior, at least on a moment-to-moment level.

A little off-topic: but does anyone who has tried Google Circles know if they're as easy (I've read many times that they are more fun :)) to make as Facebook friend lists? To make a list in Facebook I add two or three people to it and Facebook guesses pretty damn well who else I want on that list (presumably by doing something like approximate clique cover on my component of the social graph). Maybe other people's social circles bleed into each other more and that might confuse Facebook algorithm, but for me it worked like a charm.

This would only be true if Google wanted you to invite as many people as you can! But this is not the case; at least for now.