I know hacking is a big nono here on TBT (I am a member of the Animal Crossing NHC) but maybe I can get one of my friends to get me a few so I can destribute them to people (if they ask nicely ;D) but only if this is not planned on being released in the US or PAL region.
I doubt it will follow you like a static item. Most likely it will just sit there. Maybe when you touch it, it barks? OR using it in a fueng shui manner will make balloons appear more in town? (Like the presents in Nintendogs)