Well, in Google parlance, to "hangout" is to join in a G+ hangout. That's been a peculiar part of the G+ lingo from the beginning... http://goo.gl/HHXFqI guess that's true, or at least there seems to be a phenomenon of Google+ users who use "hangout" as a verb. I still don't know if Google likes the one-word verb, though. Here is a sidebar from the instructions for starting a Google hangout:
It is actually fine with me if Google wants to use "hangout" as a verb. That wouldn't by my choice, but when I get to be as gigantic as Google, I suppose my opinion will start to matter.
But my copy-editing sensibility tells me that if they are going to go that route, they need to proudly stick with it, as Apple did with "Think different." When they go one way on the rest of their site, but use "Hangout with players from the U.S. Men's Basketball team" on their front page, they violate rule one of copy editing: Be consistent. If you want to hangout with the big players like Apple, you can't afford to think different.