Coincidentally, I’m about half-way thru my re-read of Neuromancer as well. One thing that quickly struck me is how much The Matrix borrows from Neuromancer.
As for Japan, for those of us who grew up in the 70s, Japan was the rising industrial power. They always seemed to be ahead of us in technology. China is a rising power now, but they just don’t seem to be as, well, elegant as the Japanese when it comes to high-tech.
Having just finished re-reading Snow Crash a couple months ago it is interesting to see the differences in their versions of cyberspace.