Oh man. AWESOME if true. Pikmin 3 and AC: City Folk would be a perfect mix.
Both are two of the best new franchises from this decade.
I've always hoped AC Wii would be like this: people create their own town that multiple people can live in, but this time people from online can visit them. The game is constantly online.
The big difference, of course, would be that your friend in real life, in another city, can live in your AC town, thanks to the game constantly being online.
And in the game, there would now be a few BIG cities (hence, City Folk -- I hope). Big Animal Crossing metropolis. Maybe 5-10 different big cities to go to, in a way could be their own servers, in case one city has too many people currently in it. There could be malls, restaurants, museums, etc. But everyone can go to these cities and interact. Meet new people, maybe let them move into your town. (Though, knowing Nintendo, they wouldn't allow that. Ugh.)