I just swung by Circuit City and picked up two (one silver and one blue) and a copy of Mario Kart! Now I just have to wait until Christmas to play, or until my wife caves in and wears her Christmas present first!
It's still $99 on the Target site, but it's not in their regular product listing, it's in the weekly ad/holiday catalog. From the Target.com home page, click on 'Weekly Ad' in the top left of the page, then enter your zip code (if you haven't already), then click on 'Holiday December Catalog' and search for 'nintendo' or 'ds'.