Why this sudden halophilimania? Well, Japan has a reactor that's about to go nuclear, and China is Japan's next door neighbor. The logic goes: the nuclear plant will explode, thus contaminating the sea water; the ocean is where we get salt, thus salt will be contaminated by the nuclear waste; sea salt will forevermore be radioactive, so stock up now. Imagine green, glow-in-the-dark salt... There's also a rumor that the iodine protects against nuclear radiation. This resulted in millions of Chinese going to their local supermarket and buying 100 kg of salt each. They then turn around and sell it for eight times as much!
The joke's on them, though. According to the Chinese government, only 20% of salt in China comes from the ocean, and there's tons of salt in storage by the government monopoly. Not only that, with the way the currents run, it's apparently impossible for nuclear pollution in Japan to contaminate Chinese waters. What is more, iodine apparently doesn't do anything to counteract cancer, so the salt scare has been for nothing.
So the moral of the story is: The next time you hear an apocalyptic rumor, take it with a grain of salt.
For more info, check out this article in the LA Times.