I have to say that I'm not thrilled about this. The next Nintendo console will come out in 2012 as the 360 and PS3 are reaching the end of their lifecycles. But even if this system is set up to compete with the other two consoles, I don't foresee developers flocking to develop on the console and then down rez for the PS3 and 360. If anything, this new console will get imports designed for one of the other two systems.
This also means that when the next Microsoft and Sony systems come out (rumors point to 2014), the Nintendo console will be behind in hardware again.
And if their market are the casual gamers and families? I get the feeling that they're going to lose out more and more to the mobile and web markets much in the way that the DS and PSP are. Games that require the motion controls of the Wii such as Just Dance do well, but as with the Rock Band/Guitar Heroes of the past, there will be a point where no one will want to buy a new game just for new songs.
I wish Nintendo the best of luck, but I see a long uphill battle in their future that they just can't win unless they evolve agressively.
I'd recommend checking out the April 15th episode of Weekend Confirmed or the Extra Credits episode "Consoles are the new Coin-op" for insight on where I'm coming from.