I am not worried about getting cancer, sprouting another arm, the house collapsing around me, or falling into the ocean. Or Godzilla or Mothra, but if they can put off trampling Tokyo until the current situation has been resolved, that would be peachy.
I'm under the impression that rumors and misinformation or misleading information are in abundance. Take anything you hear in the American media with a grain of salt, you know how much they love sensationalism.
I've been keeping an eye on CNN, BBC, NHK, Aljazeera, and Kyodo News. I'm having trouble keeping the time zones straight to make sure I'm reading the most current articles because CNN updates in EST, BBC and Aljazeera are on GMT, NHK and Kyodo are on JST, but Kyodo News seems to be the most up-to-date 24 hours a day. Bonus, it's in English so I can understand it!
Things in Fukushima are bad, but there is no reason to panic. This is partly because I live far enough away not to be directly affected even in a worst-case scenario, and partly because I have an enormous amount of faith in the Japanese people and government to keep their shit together (pardon my language).
I haven't heard a single account of looting happening anywhere. In Tokyo, when people were stranded at work, convenience stores gave away food and drinks. A friend living in Shinjuku said that all the alcohol and food were gone from the shelves, but there was plenty of tea and water.
The train system was shut down for less than 24 hours and is now operating normally (as far as I know).
Buildings are designed to withstand earthquakes. The house we live in is built about two feet off the ground, out of wood, so that when the ground does shake, it can pivot on its corner points and the whole house has some give and flexing ability so it doesn't crack or collapse. Office buildings and skyscrapers also have earthquake resistance built into their bones, although I can't elaborate on what those features are.
As of this morning, the earthquake was reevaluated as a 9.0, making it the fourth-largest quake in terms of magnitude in history, tied with one other. Casualties here were a small fraction of what they would have been in a less developed, less prepared country.
The tsunami was bad. Very, very bad. The last I heard, 9,500 people were unaccounted for. Casualties may have topped 2K. But it struck mostly suburbs and farmland; the city of Sendai is mostly intact. The city of Tokyo has some cracked pavement, but I don't think anyone died or lost their home. The whole thing could have been so much worse in so many ways.
Now there's the drama of the nuclear plants in Fukushima. They have evacuated 180,000, but the actual distance evacuated was 20km, or about 12 miles. (Source: Kyodo News) So far, a handful of people have been exposed to radiation, but just a handful. 20-30, compared to the hundreds of thousands of people that live in the area.
This will not be another Chernobyl. It's not the same kind of plant, that design was widely regarded as unsafe to begin with, and the environmental impacts occurred through explosive release of material into the air, not from a melting reactor core. (Source: BBC)
Three Mile Island experienced a partial meltdown, but there were no deaths or injuries to workers or people living nearby. (Source: Wikipedia)
To be clear: relax. You can be concerned, but do not worry and do not panic.