CNN was saying the explosion was near the plant, not at the reactor. An explosion in/of the reactor is such an incredibly remote possibility that it's hardly worth even thinking about. Chernobyl was a horribly designed plant that wasn't maintained properly and run by people who made mistake after mistake reacting to the situation. This is a modern plant that, in the case of a meltdown, should be almost completely self-containing. Freaking out about the plant isn't called for at all.
*edit* Look at what happened when Three Mile Island melted down... external to the plant, nothing. TMI is still running the other reactor at the plant. No one was hurt. All that happened was it ruined that one reactor and showed that the safety systems worked, but everyone freaked out anyway. I suppose it's possible that this event could be a bit worse than that in a worst case scenario, but that's considering the plant got nailed with a freakishly nasty series of earthquakes and a massive tsunami. It's still, in the worst case scenario, not going to come anywhere near the events of Chernobyl.
Sorry, but depending on how this $h! blows across the ocean, I'm in the line of fire for radiation exposure. I want to know what is actually happening so I can prepare accordingly to protect myself. And I certainly don't trust the US government to tell me the truth, either.
Since Sendai is like 5300 miles away from you, how much radiation are we talking? An X-ray? A fraction of an X-ray? A PET scan?