Up front, the situation is serious, but under control. And this text is long! But you will know more about nuclear power plants after reading it than all journalists on this planet put together.
Please read this. I don’t know how it is elsewhere in the world, but the US media is having a field day talking about ZOMG MELTDOWNS. You can practically watch Brian Williams biting back the urge to ask their pet “experts” “WHEN CAN WE EXPECT THE FIRST ZOMBIE MUTANTS?”.
Nuclear power is scary shit, yes, but the Japanese are (unsurprisingly) a lot better at building reactors—and a lot more interested in preserving lives—than the USSR was.
EDIT: It is also worth remembering that even the Three Mile Island meltdown resulted in no significant rise in cancer in the subsequent 25 years.