I completely agree with you, in my weak opinion, this is perhaps the biggest step towards global implementation of bitcoin.
If Japan are successful and prove it can Be done then I can see man that neighbouring countries like N Korea, china, India jumping on board pretty soon within the next few years....
We only needed 1 major developed country to do this. It sets the standard. Now the decision to follow suit becomes MUCH easier for the other countries. It's a herd mentality. No one wants to be wrong, so they don't take the first step. But once the first step is taken by someone else without any flack... then why not join on in :)