Nintendogs has been hugely sucessful on the DS, so it makes sense to me that will see at least one Wii game in the same mold. I don't think they will do the same thing again even on the DS but the idea will be there.
Two ideas I have:
WiiQuarium
This would be the kind of collection/raising sim that we are all familiar with but mentally it fits better with the sedintary nature of the home console versus the portable DS. Hundreds of type of fish would be avaiable, real and imiaginary from classic Nintendo games. Through breeding and internet your friends could swim by just like with Mii. Nintendo might make this a Wiiware title that could be a simple channel and set as a screen saver. Imagine turning that big screen in your living room into a faux fishtank when not in use. People already buy those fake fireplaces and aquariums on DVD. Why not?
WiiZoo
This would be much like Nintendogs but the diversity of exotic animals found in a zoo. Once again they don't have to all be real. There could be Yoshi's, Chocobos, etc. A ZooTycoon like structure is possible but I don't think Nintendo will stray far from the core animal raising concept.
Final* Word on Game Delays:
The game will not be any better or include more content then planned. Any commnets that say so are just PR hogwash to make you feel better for having to wait.
Delays are due to lack of proper resources, skill, or adequate planning by the developer.
Do be thankful that they have enough respect for you to delay the game and maintain its intended level of quality.
*naznatips is exempt
