For one of the first games I ever had on my Wii, it was pretty enjoyable. This was my first true exposure to Mario Kart other than Mario Kart DS. I have to say I was pretty surprised by the amount of depth put into the game. While I did play mostly with the Wii Wheel accessory, I tried the Gamecube Controller settings as well. I stuck with the Wheel because it felt more comfortable.
From a gameplay stand-point it is pretty rock solid. You race around the tracks, dodging your fellow racers and the various gimmicks for the tracks. Some tracks I would like to forget about, Mushroom Gorge comes to mind first, but it was still solid racing. The AI for the computer controlled racers though was quite bad though. The term rubberband is not a fitting term as these things will stay stuck to you for the whole race. Usually the same two racers will follow you for a cup (in my case usually Toad and Donkey Kong, sometimes Bowser or Daisy). Still, the motorcycles are fun to play with and I enjoyed them.
The music was good and the graphics were great for the Wii. My only complaint is some of the sounds were annoying. Mainly anything that has to do with Daisy and her voice that could kill a man.
Racing around a Mario themed world should be fun. Even though the AI can be a bit brutal and often times you will go from 1st to last in a blink of an eye, it was still an enjoyable game. I only wish I had unlocked all the racers.