I've seen the exact opposite iOS vs Android numbers for Japan though I have no theory on why there is the discrepancy. And it's worth noting that the fancy phones a lot of people have in Japan don't count as "smartphones" so only 25% of people have "smartphones" vs 40-50-60% of the market in other nations, in other words there's more scope for these numbers to change (in either direction), assuming the Japanese move to "smartphones" en masse.
http://news.cnet.com/8301-1035_3-57497144-94/android-apple-t...