Look out Facebook, here comes Google+. After three months as an invite-only service, Google+ has thrown open its door to the world and rolled out a slew of new features. The announcement comes just days before Facebook’s annual f8 developer conference and seems clearly aimed as a shot across the social network giant’s bow. Let the social wars begin.

Of course Facebook has already weathered at least one of Google’s attempts at a social network, the now marginalized Buzz (two if you include Wave). But this time around Google has done more than roll out a Facebook clone. As part of Google’s att...