Viewed close up the cluster of geo-tagged tweets from London is hard to recognise. There is some clustering but it would be difficult to tell what is going one. Tweets seem somewhat random and spread out on this scale.
But as we zoom out further we started to see a concentrated structure, a cluster around London becomes easier to see.
And as we zoom out much further we can see obvious structures. Tweeting is clearly structured on the scale of nations or states, but as we zoom in closer and closer the world becomes more chaotic, harder to precisely predict. In this way tweeting is something like quantum reality. Our world seems extremely uniform view on the scale of planets, but as we zoom closer and closer in to the particles of reality they become more random and harder to predict.