1) Do the exact opposite of what hardcore gamers want.
2) Rake in profits.
Seriously though, I think Nintendo should stay with what made the Wii popular. If they just do HD and online, they will fail miserably.
One thing I expect them to do is to make the next Wii more of a media center. It would be nice if they created a TV input on the next Wii and then actually allow you to change television channels using the Wii interface. I would also expect Blu-Ray or DVD playback,
But, because this is Nintendo I would expect more than that. How about this: