Nintendo distributed this information in a news update on Switch. The notice is officially titled “The bestselling Nintendo Switch games of 2017.” However, at least for now, we have to operate under the assumption that the data is based on eShop sales in the Americas only. There are no similar notices in other territories like Europe or Japan, and the bottom of the post mentions that the news was distributed for Nintendo Account holders in the Americas.

1. Zelda: Breath of the Wild

2. Super Mario Odyssey

3. Mario Kart 8 Deluxe

4. Splatoon 2

5. Mario + Rabbids Kingdom Battle

6. ARMS

7. 1-2 Switch

8. Minecraft: Nintendo Switch Edition

9. Stardew Valley

10. Snipperclips

11. Sonic Mania

12. Pokken Tournament DX

13. Super Bomberman R

14. The Elder Scrolls V: Skyrim

15. Ultra Street Fighter II: The New Challengers

16. The Binding of Isaac: Afterbirth+

17. Xenoblade Chronicles 2

18. Puyo Puyo Tetris

19. Shovel Knight: Treasure Trove

20. Overcooked: Special Edition

Source 1: Switch News

Source 2

Nice to see that digital only games appear to be selling well.

"1. Zelda: Breath of the Wild

2. Super Mario Odyssey

3. Mario Kart 8 Deluxe

4. Splatoon 2

5. Mario + Rabbids Kingdom Battle

6. ARMS"

Arms has sold 400k units in the U.S. as of VGChartz's latest statistics. This basically proves that Mario+Rabbids is at least at the 400k mark in the U.S. I'm not going to harp on this too much because a lot has already been said, and we basically already know the numbers will be adjusted anyways, but it's nice to get official confirmation. The acception to this of course is if Mario+Rabbids has a really odd digital attach rate that is abnormally high to the point of effecting physical sales dramatically. 

I wish Nintendo would post other sales numbers up. I want to know how bigger games like doom are doing. But I am also interested in the smaller games too like steam world 2. There has to be at least a few titles that have 50k plus sales.

I think I was right when I said that Skyrim wouldn't crack 1 million WW. I think many people overestimated that one.

They usually post it at same time as their financial report. But they rarely report on third party games. Usually just 1st party. So best bet is the company who made those games to report its sales. 

Xenoblade 2 is too low. I know it just came out but still

Nice to see mostly titles I like on this list.

Ugh 1-2 Switch, you will never be Wii Sports bye!

Didn't expect Doom to hit top 20, but hopefully it did well enough

1st five are expected :p

Sadly, this list gives so little info and confusion that it's almost useless. Glad to see the best Switch game at the top tho