Remember thinking "Hmmm, multiplayer is getting old and there aren't enough courses" ? Not the case with this game.
There's no way this works on paper. 3-D Mario Kart, but with no control stick, fewer characters, and online. First of all, i thought Mario Kart Super Circuit for GBA or whatever it was called was totally unplayable; I hated not having a control stick. Good thing I borrowed it from someone. But, the control pad is extremely responsive in this game, weird as it sounds. Second, the one thing that kept me playing in Double Dash!! was its vast platoon of characters. Dude, that thing was loaded with characters. Petey Pirhanna? Talk about a minor character! But this game does have a good 12 characters, and that's just enough. And the online just blows you away. You have to try it to believe it. It's a fully-fledged online game, with complaints about "snakers" and omgwtfbbq. But the thing that really puts this game over the edge is that it has twice as many courses as any Mario Kart before. It has 16 new courses, Waluigi Pinball owning them all, but throw in four courses from each of the four previous games to total 32 courses. Now it takes you twice as long to beat it! ^_^ So if you have a DS, it's a shame you don't have this yet.