That color difference, I noticed it too. It's the only thing I found suspicious, other than, of course, the high capacity.
And the "first in Japan" thing is possible too. It seems that sometimes, better products are marketed over there, and the U.S. market is left out of the loop. I have seen that some Mini-Disc player/recorders are made available only in Japan, so why not batteries too?
I could really use a hi-cap nimh like this for my gps, it is very hard on batteries, I carry two extra sets with it.