While trolling around the internet attempting to find hard data on what sort of radiation levels we are seeing in Japan I found this site where someone is graphing radiation levels in real time in Tokyo.
The site is in Japanese but you can translate it using google translate or other services available on the web. While the graph shown does show an increase in radiation levels it is only ~4 times the background level which is very minimal. This is good news compared to the other reports coming out of Japan regarding the radiation leaking from the stricken nuclear plants. It is important to get factual data about what sort of radiation levels are being detected and where and unfortunately it has been hard to find so far.
If you can pass along any quantitative data I'd appreciate it.