I'm not sure I would class some of those countries as 'major' ... but there is a general sense now that bitcoins are leaving the USA, and at an accelerating rate.
I also think same as you not sure if many country participate in situation but i predict someday bitcoin make global function in all country because its used in transaction and in paying also
I think right after one of this "major" countries will accept bitcoin on government's level other countries will follow one by one to not stay on the side of progress. I have heard that Russia plan to adopt bit coin in 2018 year. As always they want to be first, but we will see what kind of results it will bring to them.
In Russia, the situation with the cryptocurrency remains incomprehensible. And all plans remain only plans. They have long been trying to pass a law on the cryptocurrency, but they have not yet accepted it.
I hope this issue about acceptance of bitcoin on Russia will be fix very soon. If I'm not mistaken they are one of those countries that prohibited bitcoin for a short period of time but suddenly they removed that precaution about bitcoin and instead right now they are trying to adopt, hope this will be good in no time.
Russia did ban bitcoin for a little while but as of November 2016 bitcoin is considered "not illegal"
Not sure where they are at with their btc tax laws.
That means no one can ban the bitcoin, remember if the russian is one of the biggest countries. Chine is also trying to implement a tax for bitcoin.
As far as I know if another country such as south korean is trying banning the bitcoin from his area.
It could be a wrong way to ban the bitcoin. If they're realized it can't be banned anywhere.