While the things that lead up to trends and historical events seem obvious in retrospect, predicting things that haven't happened yet is much more challenging than it might seem. People shouldn't be so arrogant when they make overconfident and often pessimistic forecasts about the future, because no one can foretell the exact course of events. When you are correct, you may appear to be a big shot, but tweet something that ages like milk and you may end up on a list just like this. We've gathere…