Obviously you were concerned enough to measure if there was any imminent danger
I wasn't concerned. I'm just a curious geek who happens to own a logging Geiger counter.
The issues is not radiation emitted, it's the radionuclides emitting them.
That is true. Ingesting radionuclides is definitely a much bigger problem than external exposure.
That's great but it's more likely that Japan now has very high concentration of radionuclides in very specific places in the ocean or land or sea, some of that area will be producing food. The likelihood of encountering in the food chain is now higher than the initial accident because the radionuclides have propagated further up the foodchain so if you ate food in Japan the likelihood of ingesting it has increased. The longer you stay there the more you will increase your chances of a permanent dose in your body, the more times you get one of those means the probability of some sort of cancer increases. A big problem for the locals, but not really a worry for you.
It's hard to get real data about these issues, as there is a ridiculous amount of fearmongering in the media. For example, there are plenty of articles talking about the spread of radiation in the Pacific Ocean from Fukushima to other countries, but a simple dilution argument shows that any claim of danger from that effect is nonsense - the ocean is ridiculously bigger than the quantity of radioactive water released, and even if you can measure the effect, it's going to be negligible in practice.
Locally produced food is another issue, and yes, the possibility for concerning contamination exists. Supposedly, food is tested in Japan, and the limits are stricter than in the US. Converting that into the probability that you will eat something that exceeds the limit (and by how much) is tricky. If you know of any serious studies attempting to calculate this, please do let me know.
FWIW, I do plan on moving to Japan in the not too distant future.