....eh, not really.
Armageddon, the story of how the world ends, is the most important story of all. It's the basis of all religions, and one of the most common themes in storytelling.
As God is losing respect as a force for complete destruction, now we turn to other stories about how we will all die. Meteor from outer space, atomic winter, Y2K, robots taking over, technology going awry, genetic engineering, global warming, overfishing, overpopulation, and other forms of ecological disaster.
It's whatever seems plausible at the time. In the 50s, technology going crazy became a common theme. On December 31, 1999, technology failing due to a simple rounding error was more plausible.
But the reaction I think you should always have is:
NAHHHHHHHHH.
Armageddon has been predicted SO MUCH, and has NEVER come about, for a reason: when you add the end of the world to a story, people listen a lot harder, and share that story a lot harder.
That's all. It's a thing: ideas spread when they are considered important, and here is the most important thing of all. But so far, so good: after millions of predictions of armageddon, all seeming plausible, it has never actually happened. (Duh.)
And now that we have more educated experts than at any time throughout history, it's more likely that we can plan around or fix things, well before things are going desperately wrong. But as stories go, the story where mankind uses its hard-fought knowledge to fix everything is not a story we enjoy repeating. So you won't hear that prediction.
Remember this as you go about the Internets, and you will notice the predictions happening... and the world will be much less scary!