Here's some facts...
It's on track to sell 1.25 million in the US on week one (the highest one week total in nearly 10 years and the second highest female debut of all time behind 'Oops I did it again' by Britney Spears, which was in 2000 when record sales were much higher than they are now).
It only going to sell ~250-300k in the rest of the world though, so your '5-6 million' worldwide in week 1 figure is bullshit.
Still, in this day and age when piracy is so widespread, her US sales are astounding, and could perhaps eclipse Britney Spears record and become the highest selling 1st week for a female album ever.
My prediction threads:
Wii U will sell under 40m units (made on 14th September 2012)
PS Vita will sell under 20m units (made on 30th September 2012)
Wii U will sell under 7m in 2013 - I was right