I've never had so much fun in a multiplayer racing game before Mario Kart DS.
Mario Kart, back then, and now, is fantastic. I've never had so much fun in a multiplayer racing game before Mario Kart DS, and the WiFi mode allows you to play online with people across the world which is pretty damn good. The graphics are detailed and the music and sound effects fit in very well.
The actual playing of the game is excellent and great fun. Hitting the random items box and unleashing your item in the right way against your opponents adds a lot of fun. It takes practice to race like a pro, though the game eases you in.
There is a lot to see and unlock in one-player mode, where it's hard to fault the game. Online play could be improved a little, as there are only a limited amount of tracks available to play on. One gameplay issue to note is that it is possible to 'cheat' and speed boast along any straight sections of the track by using a technique called 'snaking', whereby you slide side to side allowing you to boast. To most Mario Kart DS players this is seen as cheating as it takes away a lot of the fun of the racing by giving 'snakers' an unfair advantage. So please don't snake.