It might be where they're measuring. He went on to indicate that at the gate, the measurements had just reached the milli- level; perhaps the exorbitantly high figure is very close to the core?

I think the figures that were thrown around in that press conference--either by Edano or 'white lab jacket guy'--varied by location however the translator had my head spinning and I couldn't deduce what's what.

I'm pretty certain that anytime "600 to 800" was mentioned, it was supposed to be in uSv, and that those measurements were taken at the plant's gates.

Fair enough. Will be good to see a correction, then (like that'll happen) -- most of the big names in the media have already run with milli-.

Takeaway for me from this: units for radiation exposure suck, and don't communicate well to the lay.

I'm willing to bet they will repeat that news conference on the hour (one minute) on NHK:

http://www.ustream.tv/channel/nhk-world-tv

EDIT: They indeed did so, but shortened and dumbed it down with only 2 figures being provided by 'WLJG'--2.3 and 6.4 mSv 'near the plant', with the latter being the peak at the time of 'leak.'

There's no point endlessly debating the numbers since Tepco releases them in full:

http://www.tepco.co.jp/tepconews/index-j.html

Here are the latest ones for Fukushima-daiichi:

http://www.tepco.co.jp/cc/press/betu11_j/images/110316c.pdf

The columns are, in order, date, time, location (often 正門, the main gate), gamma rays, neutron radiation, wind direction, wind speed. The latest peak seems to be 10.85 mSv/hr at 12:30PM on the 16th, down to 2.5 mSv/hr less than one hour later.