Certainly, it's endearing. It just isn't enduring.
The Bad: You'll see everything there is to see in about a week or two; talking to your DS looks crazy; bland backgrounds; repetitive but catchy soundtrack; monotonous tasks.
Nintendogs is one of those games that's PERFECT for the non-gaming crowd. It only requires a little bit of devotion, and it's not hard to get into. It's plenty simple, and it's not as big a hassle as a real dog (though real dogs are wonderful!) And the game is very appealing and intriguing. The trouble is, within a week or two of play, you'll have seen everything there is to see here. And no amount of personality or quality can make up for that.
You start out by picking a dog from six available. Then, you take it home and give it a name. It's up to you to feed, clean, train, and walk this dog! You can get more dogs after earning money in competitions, and you can upgrade your house. It will only take about a week to win every competition, though, and get the house you want. Then, there's just nothing else to do. Nothing. Why get another dog? You have the one you want, and it knows every trick in the book. Walking, feeding, and cleaning all get old quickly. Frankly, it would have been nice to see more variety and options in the game. As it is, it's lacking in lasting value.