But apparently there's a lot more to it. At the moment the game is in alpha, which in typical Google SOP means you have to get an invite to play the game. Atypically, acquiring an invite is less about finding someone you know who has it (ala Google+) and more like passing an audition. Basically, you can wait at one of the metered portals for an invite or send a cool picture, tagged with "Ingress" or one of the other popular hashtags for the game. This is my friends work:
So it appears he was successful, nice work!
The actual play clips I've seen make it seem like a combination of geo-caching and Layers and also a bit of a road hazard, but still...very interesting.
Seriously I'd check out all four of the links below, there are some really creative artifacts people have come up with.
Apparently this is a major initiative at Google and it's not hard to see where this is going. Add augmented reality game that encourages people to walk around cities looking for obscure public art, add Google Glasses so the game overlays create a more seamless experience and then plug the occasional paying advertiser. I don't say that as a criticism. If it works, this could portend all sorts of Neil Stephenson-sque, Snow Crash Metaverse style developments.
As promised here are those links as well as as a link to the article about Ingress.
Anne Beuttenmüller, Joe Philley, Brandon Badger, Brian Rose.
Data-mining as a Game