Man this game freaking rocks because it's more about skill and precision rather than item throwing (A la MArio Kart) Plus:
The soundtrack is awesome. Ex.: Captain Falcon, Bio-Rex, Digi-Boy and Princia Ramode Theme's
The sense of speed
The courses (My fav being Cylinder Knot)
And the wide selection of characters
I own the game (Got it used at gamestop for 12 bucks in almost perfext condition) and still play it (mostly because I haven't finished the story mode, It's murder really the difficulty on normal I might add) and it is still loads of fun