This is reeeeally encouraging for the future of the series. I hope it crosses 1m on its first 6 months so it sends a message to Nintendo.
If we are lucky, and sales are as good as japan in the other territories, it probably already passed 1 million worldwide, even if that number is shipment.(As Europe does around Japan number and US does more than double that)
My (locked) thread about how difficulty should be a decision for the developers, not the gamers.