Paro the robot seal is actually the best of all robotic pets. How comes it is only 7th then? Well, you just can't get it, which makes it slightly less cool.
Nao is more than robotic pets: it is a baby robot! Sounds creepy? Just look at his cute face and you'll understand how it could charm all your family so easily.
Here are some cheap and interactive robotic pets. Since their creation in 1998, the Furbies have been instant success with every kid, and even the parents love them.
I think the bigger debate is how much personality and emotions we can give to robot pets. Since I think that robots can equal human intelligence one day, I think they will equal pet intelligence even sooner.