[Update: Nintendo of America has released more details, mainly that both downloadable content packs will cost $7.99 each, or $11.99 if you buy them together. Pre-orders are now open and they grant immediate access to the new Yoshi and Shy Guy colors.]
Whoa! The official Nintendo UK Store website has a listing for upcoming Mario Kart 8 DLC that will add characters and courses from other Nintendo properties, including The Legend of Zelda's Link, Animal Crossing's Villager, and a kart based on F-Zero's Blue Falcon.
The first pack releases in November and includes Link, Cat Peach, Tanooki Mario, four vehicles, and eight courses. Then, in May, the second add-on introduces Villager, Dry Bowser, Isabelle, four more vehicles, and eight new courses. The DLC packs are priced at £7.00 each.
"As a bonus for purchasing both packs -- as a bundle or separately -- you can get eight different-colored Yoshis and eight different-colored Shy Guys that can be used right away."
It's about time this happened. I'll be dying to boot up Mario Kart 8 again come November.