Brave if true. DFAT says Japan is OK but to defer non essential travel. QF says it's OK- and let's be honest, they've proven recently that they don't mind pulling the pin if they have doubts and given the recent loads they'd probably be thrilled to not have to fly a half full jumbo to/from Japan. There is no risk to anyone in Narita.
The nuclear risk whilst real for those working at the power plants affected isn't really a big deal for the rest of Japan- unless you're a journo looking for a doomsday story.
If you're after a more informed point of view, try
here.