I'm guessing that you are referring to political revolutions? I would say they are nigh on impossible to predict as if there were obvious it is likely none of them would succeed. Looking more than a few years into the future is always dangerous. Who at the beginning of the twentieth century would have predicted we would have the power to destroy our own planet 60 years later, who after WWI predicted WWII, who in 1980 predicted the end of the Cold War?
If I were compelled to put something forward, I would suggest a change in the way states relate to one another as they move into more consolidated regional entities such as the European Union. Hardly the similar to the French revolution, but revolutionary in its own right, especially if you are a realist.