Rather alarming, isn't it! Obviously a long way off on an individual scale, but not so much on the historical... :/
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
Rather alarming, isn't it! Obviously a long way off on an individual scale, but not so much on the historical... :/