shazam - 12:42 am on Sep 1, 2011 (gmt 0)
It's for more than just ranking.
For the people legitimately using it, Google+ is really just another ideal tracking tool. What better way to easily keep track of users surfing habits and preferences. The sheeple just blindly give this info to g without a second thought. Meanwhile the webmasters help out by putting the spy code on their sites in the hopes of getting a treat.
It's really quite a brilliant data mining technique. Before now, it was a challenge to get direct access to webmasters data if they weren't using g analytics. Now they willingly put the g code on their sites and even pay people to make fake plusses.