I had no idea what Latitude did until I read this article, other than tell Google where I am. I turned it on though...just to piss off all those people that think corporations are taking over our lives. Naturally I'd turn it off if I were to invade Russia or do something that they'd actually care about.
Great Googlies! I hope that this is opt-in. Otherwise, Big Brother is here. Well, Google already was, posting pictures of everybody's house and claiming exclusive rights to all the books in the world.