Kart. If you liked the MK series more, then go with your gut. It's Nintendo. The games don't change. (Oh, you know what I mean)
Also, I perfer Kart, and all the complainers who say it's luck based don't understand the concept of Mario Kart. Luck plays a role, but not as big as people make it out to be. Either that or they expect to get 3 star rating the moment they touch the wii wheel... This does not, however, affect my eternal love for Brwal.