45m-55m before its successor.

A safe guess is 80-110 million. I'd be surprised if it sells less than the likes of ps3/360/psp, and somewhat surprised if it gets passed wii/psx level.

50 million with an almost impossibly better attach rate of games and accessories per system sold. A Switch case and Pro Controller are almost mandatory buys at this point. By March 03 2019 Switch could easily have a better library than the Wii U's entire life-cycle. We're not even five months into Switch and there's easily six to seven good games on store shelves. At this point Wii U just had Monster Hunter, NSMB, and Nintendoland.

60-65m is what I'm thinking, but depends largely on how many year Nintendo will support it/release a sucessor

You reminded me, now I'm sad. :c

90 million.

I agree. No Nintendo system has ever sold more than 85 million before anyway.

My prediction is around 68m currently.

Way too early to predict the endgame, as a lot of people at first figured the Wii U would sell 40 million plus consoles. I'll bite anyway.
January 1, 2018 - 10 million units
March 31, 2018 - 12.3 million units
So it will surpass the Wii U in the second quarter of 2018
Final Sales - 55 million

Over 110m