The Switch version is a third entry, much like we've seen in past generations with the 'main' games, and will be called Pokémon Stars. It has apparently been in active development alongside the 3DS edition, paused for a short while as Sun and Moon were polished, and will naturally boast vastly-improved visuals.
In fact, Eurogamer believes a snippet of Pikipek concept art from the February reveal of Sun and Moon is from the Switch development, according to its sources.
As a third entry it'll "feature the same map - the same routes and cities - and the same art style, although be built using separate, higher-resolution assets". Also of note, reportedly "Pokémon will be tradable between Sun/Moon and Stars via the Pokémon Box app." New monsters and content are also in the works, apparently.
It'll be separate enough from Sun and Moon to avoid detracting from them, it's being stressed, and it's not imminent either. Eurogamer's sources have stated that a targeted Summer 2017 release has been push back to later in the year. It is the core Game Freak team producing the game.
Whenever it comes, a mainline Pokémon title would certainly bode well for the new console.
Will this news impact your purchasing decision with regards to the 3DS version, or are you happy to play through a new version in 2017 on more powerful hardware? Let us know by posting a comment below.