No doubt there will be an animal crossing for the wii, and no doubt it will be great with the added value of the internet. Anyway, i think it would be really good if this version was in first person. You would look around from the characters viewpoint, and this could be done very easily using the wii-mote. For example, you could use the analogue stick on the nunchuk to move around, and change your view and point at things via wii-mote. I think it would be really good shooting down 'presents' in the air, etc from this viewpoint.
The only disadvantage would be that you couldnt change your apperance, or at least there would be no point in doing so, and i think changing clothes/haircut was very good in animal crossing's so far. Any ideas?
I also think there should be lots of minigames, that you could also play with visiting friends via wii-connect. You could use bells to play small aim-and-shoot games, 'throw-the-hoop' etc and win prizes. (You know, the sort of games you may find on super monkey ball etc)