Well at least like 95% of people I was talking to said the Switch is the first Nintendo Console since the Gamecube they actually consider buying. Most of those are PC enthusiasts, skipped Wii/Wii U and the Switch offers something different. For those people the PS4 (aka Bloodborne machine) and XBOX one are trying too hard being a PC but worse and the Wii/Wii U is too gimmicky and the 3DS just uncomfortable and has a terrible screen resolution/graphics to play at home over using the PC.
The Switch however has a resolution that allows good picture quality (pixel density will be higher than on the first Nexus 7 I still have and that's EASILY enough (I take 720p/60fps over 1080p/30fps any day) and also has the engine to power modern games with support for important engines like unity/unreal engine 4. Also it might bring us a lot of Nintendo Exclusives we were waiting for on the Wii U like Metroid or even Diddy Kong racing.
If the price is right (~300$ or €) and Mario comes shortly after Zelda, I see this thing selling well from the beginning. If we get 3rd party releases as well even more so. Maybe the already existing Tegra X1 games are re-released as well like borderlands/metal gear rising/etc. Those are not "new" games but playing it portable is a bigger selling point than some may think. The Tablet is not that big. I see a lot of people on train with their iPads or ebook readers which are not that small either and for children this is also looking like an attractive product. It's a tablet, something a lot of kids want AND a gaming console. Nvidia couldn't deliver their vision to the masses with the Shield series, but with an influential gaming company like Nintendo this might really take off. We have seen how much hype a mediocre proof-of-concept demo called pokemon go could build up.
