Mario Kart Live Home Circuit has been announced!
See the Super Mario direct here:
https://scratch.mit.edu/discuss/youtube/s_UcjEq2Dgk/
This was a exiting addition to Mario 35th birthday that no one expected. It was many peoples' highlight of the direct because it was something brand new and really cool.
The only problem is that there's only 2 karts available (Mario and Luigi) and they each cost $100!
Each kart comes equipped with a camera which links to the Nintendo Switch. There will be AR CPU racers generated and it will play just like Mario Kart 8 with the exception of Chain Chomp as an item and the Blue Shell regaining wings.
To create a course, place 4 gates around your room and use Mario/Luigi to drive through the gates. The game will then use AI to create a course following wherever you went in the test course.
Multiplayer is also in this game, though you have to have 2 separate Nintendo Switches and 2 separate cars. That means you can't do split screen and you can't create a virtual player. The cool thing about multiplayer is that if you get hit by the other player, your kart stops and you won't be able to control it.