Its fine.  Mario U is fun but Luigi U is the star of the package.  Some of the Luigi levels are pretty fun and tough later on.  I beat both on the Wii U when they came out and never went back to them.  One of the issues with the game besides the basic New Super Mario feel, is similar to Yoshi Crafted World where there are some beautiful creative levels, but a lot of rather plain filler levels.   If Super Mario Maker 2 didn't exist I think its worth it as a fun game, but Mario Maker 2 is flat out the better game.  In America I believe its on sale for $30 for Black Friday and I think that is a fair price for it.  If you can get it for a similar price in Sweden I say go for it. 

I'll say 13M and no; there won't be a new 2D Mario game.

My guess is around 12 million. I'll be picking it up during the black friday deals this year!

12 million, the legs have far exceeded my expectations

NSMB will hit 20m imo unless a ground up 2D Mario game is released.

+11M for sure, it's got legs but not as crazy as other Nintendo games.Give me another NSMB or at least port over the DS&3DS versions.

I'm guessing it'll be higher than 20 million, but not much more than that. So I went with the 19-20.9 million option.

Bonus Question:
Not on the Switch we will. Nintendo seems very content with just letting the Wii U Mario ports constantly sell well and rake in the easy millions they bring in. That's why we're not going to see Mario Kart 9 until Switch 2. We might still get a new 3D Mario game. But with 3D World Deluxe right around the corner, along with the 3D All Stars collection, I've gone from "likely" to "doubtful." Just like I think they're content with Mario Kart 8 Deluxe and New Mario U constantly selling, I think they'll be just as content to let 3D World do the same thing and let that game keep selling along with 3D All Stars (until the end of March anyways) and Odyssey.

The Switch is still going to get a plethora of new games, big and small, most of which I think will be 3rd party. But as far as Mario is concerned, B-C tier spinoffs like another Mario Party, Mario Golf, Mario Sports Mix, or another Mario RPG (Whether it's a new Paper Mario, Mario & Luigi, something new, etc.) is all we're going to get. I think the big, blockbuster, A-S tier stuff like Mario Kart and the platformers are being saved for Switch 2. I fully expect Mario Kart 9 to be a launch title and the next 3D Mario game within the first year of its cycle. Once Switch 2 or whatever their next system is comes around, THEN I think we might see a brand new 2D Mario game... Assuming they haven't just replaced the 2D line with Mario Maker.

I agree with all you said...except the bit about no new 2D Mario on Switch. MK9 Switch 2 launch game for sure. With 3D all-stars and 3D World and maybe a separate Galaxy 2 release at some point (??) I don't think a second new 3D Mario with hit Switch. But for 2D all we have is an old port that certainly did not sell like a normal 2D Mario game, as compared to MK8D which was clearly accepted as THE Mario Kart game for the Switch and thus why we won't be seeing another one. They also slipped out NSMBU:D as a january release as just some post-holiday filler. They are no doubt planning a new 2D Mario with all the marketing and timing that goes with some a major release. And yeah I'm sure we'll get another Mario Party and some assortment of Golf, Sports mix, etc on the Switch in the future. But it'd be truly bizarre for them to skip a new 2D Mario game on the Switch. That'd be a major game and a 20+ million seller for sure, and with just Mario Maker (which is a different kind of experience) and an old port they certainly haven't hit that spot in the library yet. 100% chance Nintendo is bringing 2D Mario to the Switch in the next two years.

Its curious this game is selling so well. Don´t forget how hard nintendo had to push this game on the Wii U era, they were retailing it for $20 bucks and people couldnt give a damn. Nintendo Switch resurrected this game for good.

Fun game and all, especially Luigi U. Probably the best of the "New" line.But 2D Mario needs to evolve. Letting people create the levels was one way, but the gameplay itself needs to change. The problem is that 2D Mario is kind of like gaming comfort food, and if you change it too much it loses the nostalgia and familiarity that people like so much.