In an interview with the Mario Kart DS producer Hideki Konno, Nintendo of Europe got us a few tiny details on Mario Kart DS. As previously stated battle mode will not be online, but on the promising side Mario Kart DS will be the first in the series to have AI opponents in the multiplayer areas such as battle and VS. Unkown if they will be online, but it seems both unlikely and unnecessary. There are 16 classic tracks and 16 all new ones, one of which is a giant pinball machine in which you must dodge moving paddles and pinballs. Finally, here is the ending to the interview:
By now we have made several different Mario Kart series and I really dont want anyone to say Oh, there have been too many Mario Kart series over the years, I dont need any more.

Whenever we are making a new Mario Kart we are trying to make it something special, something new and something really unprecedented. This time we have really challenged ourselves so that this DS version will become something really unique. So I hope the members of Nintendo-Europe.com are going to play it and enjoy it!