Amnesia said:
I am totally stranger to this series. Is it like a spin off or a main episode ? I am just surprised that they drop it in a trailer and not keeping it for an announcement in a direct.

The Paper Mario series only has main games. There was one crossover with Mario & Luigi, but that's a Mario & Luigi game. 

Here's how the Paper Mario series stands.

Classic/RPG: Paper Mario, PM: The Thousand-Year Door

Super Paper Mario

New Style: PM: Sticker Star, PM: Color Splash

PM: Origami King

I separated Origami King because it so far seems to have differences from Sticker Star and Color Splash, but does not seem to be like the original two games.

Lifetime Sales Predictions 

PS4: 130 mil (was 100 million) Xbox One: 55 mil (was 50 mil) Switch: 110 million (was 73, then 96 million)

3DS: 75.5 mil (was 73, then 77 million)

"Let go your earthly tether, enter the void, empty and become wind." - Guru Laghima