In October, Switch was the best-selling gaming hardware in the US. It was followed by the Super NES Classic Edition at #2. Nintendo says that, when combined with 3DS, Nintendo systems accounted for two-thirds of all video game hardware sold for the second month in a row. The US gaming industry achieved hardware sales of more than 1 million total units in October for the first time since 2011.
Regarding software, Super Mario Odyssey was the top-selling game despite the fact that it launched at the end of the month. Mario Kart 8 Deluxe and The Legend of Zelda: Breath of the Wild placed at #10 and #11 respectively as individual games.
Source: Nintendo PR
Article: NintendoEverything
Update: Top 10 best selling software
Nintendo Switch
Super Mario Odyssey
The Legend of Zelda: Breath of the Wild
Mario Kart 8
Fire Emblem: Warriors
Pokken Tournament DX
Splatoon 2
Mario & Rabbids: Kingdom Battle
FIFA 18
NBA 2K18
Dragon Ball: Xenoverse 2
Nintendo 3DS
Mario & Luigi: Superstar Saga + Bowser’s Minions
Metroid: Samus Returns
Miitopia
Etrian Odyssey V: Beyond the Myth
Pokemon: Sun
Fire Emblem: Warriors
Super Smash Bros.
Mario Kart 7
Super Mario Maker
Layton’s Mystery Journey Katrielle and the Millionaire’s Conspiracy
(=^・ω・^=) Kuroneko S2 - Ore no Imouto - Steam, MyAnimeList and Twitter - PSN: Gustavo_Valim - Switch FC: 6390-8693-0129 (=^・ω・^=)