The video stream of the Geiger counter I posted yesterday is offline now. Of course, that causes tons of people to freak out and assume that something horrific has happened. In any case, here's another site with readings taken every 10 minutes and graphed out over what appears to be about 36 hours. Here's a snapshot of the graph:
As you can see, Tokyo is still not receiving significant amount of radiation. It sounds like the bulk of the radiation that's being reported as leaking from the Fukushima reactor is from noble gases, with extremely short half-lives. In other words, unless you're in the immediate vicinity of the reactor and stay there for hours, the radiation isn't going to significantly affect you. That's the current status; the situation is still developing, but the more I read, the more (cautiously) optimistic I am.
UPDATE (3/16/2011 12:45pm ADT): The live video stream of the Geiger counter in Tokyo is back online, and the counter is currently reading around 23 CPM.