Its downhill from here, DS Hardware has peaked – Analyst

According to Hiroshi Kamide from KBC Securities Japan the Nintendo DS hardware has reached its peak worldwide. He also believes that since it has now peaked, the software sales will fall as casual gamers are happy with their lot. But its not just the Nintendo DS that this will befall but eventually the Wii. His reasoning is that games like Brain Training and Wii Fit are not gateway drugs to turn non-traditional gamers to core repeat users. As we understand it, those arent the bridge titles (Nintendos definition) but more so the games like Mario Kart.
Source: GoNintendo