The Wii is capable of a good racing game, as you can see by Excite truck. ET may not be a true racing game but you can get the general idea that it can control as good if only someone would take those controls and add it to another named game, with more substance.
As good as I found ET I'd rather play NFS MW on the cube, not because I don't think the Wii cannot make a good racing game but so far they really have not, and this game rocks.