There are a lot of things working against Nintendo's next console the way I see it.

First there's the casual market. The thing that literally made the Wii the success it was is going to work against them in a lot of ways. For starters, these aren't people who really buy or play a lot of games. The Wii had a terrible attach rate for titles because people weren't buying games to the degree that PS3/360 owners do. In fact, I wouldn't be surprised if many never bought much more than Wii Sports and Wii Fit. The problem will be convincing these users to buy a new console 5 years later, especially given the changes in the casual landscape. Nintendo will now be competing directly (whether they realize it or not) with smart phones, tablets, browser based games, etc. These have exploded in casual gaming since the Wii came out and many who are used to using their smartphone or ipad for their casual gaming will likely be hesitant to through down the cash for a console that doesn't offer anything that different for them. Even worse is that Nintendo hasn't mentioned anything radically new (a touch screen on the controller isn't a radical innovation by any stretch) and certainly can't rely on the novelty of motion controls this time around. This is all without even getting into the fact that more powerful hardware means higher dev costs which will make it harder for companies to turn a profit on casual games.

And if it wasn't enough that the casual market will be a tough sell, they've got to try and win back hardcore gamers who are used to being burned by Nintendo, and third parties who are especially going to be gun shy after the last three generations. Yes, it will be easier to port games from the PS3/360, but it's going to be hard for Nintendo to get third party's to commit to the exclusives they'd need to really draw in hardcore gamers who likely already have a PS3 or 360, or both. And all of this will be totally moot if they don't drastically improve their online infrastructure. Friend codes are not going to cut it and they're already basically two generations behind Microsoft and one behind Sony in this regard. They'll have a lot of catching up to do, and I really don't have a lot of confidence in Nintendo to pull it off. They've repeatedly shown their out of touch with what gamers want in terms of online capabilities, from saying gamers don't want it on the Gamecube, to the pathetic implementation and community features of the DS and Wii.

Maybe they'll pull it off on the strength of their name or even more impressive, actually manage to competently address all of the challenges they have to overcome, but it'll be a hard road for them. They can't count on casual gamers, hardcore gamers or third parties supporting them with the new console unless they really give them reasons to.