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It will be a ninth generation console even if it is underpowered. Take a look at the first two Xbox consoles. The Xbox came out November 2001 and then the Xbox 360 came out November 2005. Sure it was less than the 5-6 year cycle for a console successor, but it was quite clear that the 360 was a full sucessor to the original Xbox.
The Sega Saturn came out in 1994/1995 then the Sega Dreamcast came out 1998/1999. Another fairly short cycle there, but most people call the Saturn a fifth-gen console and the Dreamcast a sixth-gen console. I think people are still debating this because if the NX comes out late 2016 it will be the shortest time for a sucessor to a Nintendo home console. The debate is also on because the competition has not even been out for three years yet.
My money is on the NX being 9th gen, but we will have to wait what history makes of it.
Lifetime Sales Predictions
Switch: 156 million (was 73, then 96, then 113 million, then 125 million, then 144 million, then 151 million)
PS5: 115 million (was 105 million) Xbox Series S/X: 48 million (was 60 million, then 67 million, then 57 million)
PS4: 120 mil (was 100 then 130 million, then 122 million) Xbox One: 51 mil (was 50 then 55 mil)
3DS: 75.5 mil (was 73, then 77 million)
"Let go your earthly tether, enter the void, empty and become wind." - Guru Laghima
