Sorry, never played nintendogs before but I have played with Tamagochis and enjoyed those immensely, I have a feeling that if I was back at that age again and I fully understand what to do here I would be into this like white on eggs but right now, I think I'm the one with teething problems.
As for fun factor, skip out on challenges and you'll have a good time, I'm not an animal lover (I actually have a phobia) but this is like having a puppy running all over the place and the cuteness is kind of heart warming.
I can probably have hours of "fun" just waving my hands around and having Dogma (my pet) chase it around. But the main issues are depth perception, lighting (I had to place a lamp directly under the eyetoy to get it to work) and slightly intrusive challenges.








