[SIZE=8pt]Tamagotchi DS is indeed a game intended for the Nintendo DS. However, given the immense popularity of Tamagotchis in relation to the Japanese market, we may not see it here. [/SIZE]
In consolation, there is a Tamagotchi game for the Gameboy Color. I purchased it off eBay recently for about $13. I have yet to play it however, so I can say nothing as to its quality.