I don't think it will be so melodramatic. Just my two cents on what comes next.
Best case scenario is Star Trek. The next overthrow is done with some level of forethought and organization, technological improvement continues to make human labor less important, and we create some workable form of socialism that makes sure the basics of life are guaranteed so that our competitive spirit is saved for better things than cooking fries. Success is measured by what you actually do rather than what paycheck you are pulling. This is incredibly idealistic but, considering how quickly society has evolved in the last two hundred years, it isn't necessarily impossible. This is the one that we want to happen even if it is a long shot.
The next mild one is a "Western Spring" movement. We work within our own governments, society doesn't change a whole lot, and all we do is bring down the especially wealthy. This seems like it would be asking for another set of ultra-wealthy plutocrats further down the road, and it doesn't really answer the looming long-term problem of technological unemployment, so I guess this could be classified as the situation where we don't really have a dramatic revolution on a societal level.
Another possibility is that we will revert somewhat. The overthrow happens, involving a revolutionary pattern likes those of the early twentieth century, so that the world economy is broken up again. Everything having fallen back, nationalistic fervor and all the room for growth created by the "collapse" pushes for a quick period of regrowth and re-industrialization. This is the world with the largest threat of World War 3, but what that looks like in the context of nuclear weapons is hard to say. We could see a replay of the cold war, but with very different factions. This one feels more likely, but it doesn't mesh historically. Revolutions usually don't involve a reversion like that. Whether it is Rome, or France, or Russia, there usually is a significant reorganization of the social order involved. Though we are talking about a revolutionary pattern that is largely global.
So it seems that the most likely event would be a more extreme version of the last one. The revolutionary pattern is more intense, and societies values change drastically. What it means to be an American, or a European, or Chinese, shifts drastically within the context of these revolutions. This means the borders change, the rules change, and we enter a world we might struggle to imagine. It's like us now are mid 18th century Brits trying to describe what the world will look like in 1900. It can go anywhere.
The worst case is a division of all known boundaries and the complete collapse of modern social ties. Nations fall. This is the Fall of Rome scenario, and it seems drastic to me because the governments of the modern world are rather efficient compared to those of collapsing empires. If this does happen, the breaking of international and national ties means we all live in some form of near-subsistence poverty. Still, the Roman Dark Ages meant a rich urban government was replaced by multiple poor agrarian governments, it didn't involve a significant loss of technology (despite what the movies say). With the technology we have to day, this complete breakdown seems unlikely.
and if tumblr takes over, who says it gotta be the shut-ins part of tumblr? maybe the porn part of tumblr takes over.