Unless a giant meteor smashes into Earth or there's a huge natural disaster that affects the entire world, then the world will not end abruptly.
I do believe however, that society, especially in the U.S., will continue to degrade. The U.S. is past its ears in debt and civil unrest has been going on for a while now. Flash mobs stealing from convenience stores and beating the store clerk down, occupy what the F- ever protests -- it's not going to get any better any time soon.
Global commodities (like oil) is traded on the U.S. dollar because it has traditionally been a strong currency. I don't believe it has happened yet, but when the other countries want to trade in a different currency, then you know the U.S. is in real bad shape. I'll throw this out: the University of Texas Endowment Fund has recently taken delivery of $1bil worth of gold (5% of their assets)... I don't mean investing in the GLD ticker, but taken delivery of $1bil worth of physical gold bars. Gotta ask yourself, why would they make a big move like that...
Michael.