I'd switch things around and offer Wii fit with the Wii for a discount package, and then I'd lower the DS's price, too, but I still feel like they need to be preemptive about this.
When you look at it, though, I'm absolutely astounded by the DS and the DS Lite. It started November 2004, and has only had one price drop, down $30 from $150. The PSP still is more expensive, but it's had several price and packaging changes, to compare. I can't believe that we're nearing four years of the DS with no price drop in sight. Honestly, I expected a drop back when we heard about the price fixing. To me, this means that the profits on the DS have got to be outstanding, considering Nintendo sells hardware for profit. We know the cost of manufacturing has lowered, so who knows how much Nintendo makes from each individual DS.