If Nintendo can make their Online experience better, they could be quite the threat with the Wii U.
Innovative controller? HD graphics? Backwards compatible? Big name games? it definitely sounds good on paper. Another missing puzzle piece is online gaming. Nintendo has never been strong here, which makes me wonder how they'll make the experience better with the Wii U. Will they make it better?
It's no longer just about online competition and game downloads, but home entertainment and social solutions as well. Nintendo will need to be able to offer streaming media services (such as Netflix, Hulu, Pandora, etc.) to their customers. Social interaction is a big thing as well. Facebook and Twitter are huge, of course, so being able to integrate those into the system (and possibly the games) will help Nintendo catch up with the modern Internet.
If they can, Nintendo's home console may not be considered a kid's toy anymore.
Of course, price also has a giant question mark on it as well.
I simply do not know if the "gimmick" this time around will stay fresh enough say five years from now for big time developers to still consider the Wii U for big time console games, or if it will be shunted off to their smaller developers to create a half-hearted attempt at a port. I'm really hoping that Nintendo has third party developers figured out by now, because if not I don't know if the general populace will fall for a Wii again - a console full of innovation that becomes mired in a sea of sub par third party titles while the "Big Boys" get all of the big game support.