Twitter has catalyzed revolutions, is regularly the first place news stories are broken, and if you’ve heard of the #hashtag it’s because of Twitter. Now Twitter is filtering tweets through an algorithm to predict the likelihood of developing heart disease in a given area, and surprisingly—or not surprisingly—the predictions are very close to the actual cases reported by the Center for Disease Control (CDC). So what’s the big deal? Well predicting heart disease can lead to prevention, Twitter can get their accuracy down to the county level, which could lead to specific preventative measures on the ground. Additionally, using Twitter’s method of prediction is cheaper than the traditional method of predicting cases of heart disease—via survey. So how will Twitter change the world next?