I think there needs to be greater emphasis on exactly how big some of this news is.
The platform unification is the biggest thing. Basically, Nintendo's "platform" is no longer going to be the Wii U and 3DS, but rather Nintendo Network. Nintendo's "platform" is in the operating system, not the hardware. Basically, it's like with the relationship between the iPhone and the iPad. The are two related divides working on nearly identical software. iOS. With that, you aren't attached to your iPhone, but to your Apple ID. When you upgrade devices, everything transfers over, so there's no rush to upgrade, and there's no fear of loosing your installed base, because your installed base is not the Wii U and 3DS, it's Nintendo Network and it's NNID. It's literally a fail safe. And a clever one.
Why this is genius is because if they release the successor to the Wii U/3DS sooner than we expect, it basically eliminates backlash. Because everything will transfer over anyway, it's basically taken in the same way as upgrading your phone. The hardware itself doesn't matter. It's the OS you're purchasing. The hardware just happens to run it. Now, the same way all your apps and music will transfer over when upgrading to the next iPhone, they want to instill that same feeling when upgrading Nintendo hardware. You're just transferring you NNID and all of your games onto newer hardware. Everything is backwards compatible. And since everything will grow digital, there will be a bigger attach rate to upgraded hardware.
This also finally brings the reason for the gamepad to light. It has nothing to do with casuals or tablet gaming. It's much simpler than that. Platform uniformity. Everything you can do on the DS, you should be able to do on the Wii U and 3DS and every new system onwards. It has to be that way, or else this whole OS thing doesn't work. Everything must work on the same hardware and be able to jump between. That doesn't work when your home console is missing fundamental hardware like the second touch screen.
It also confirms that the gamepad is never leaving the Wii U, and that it's guaranteed on it's successor. Every new Nintendo console will have a tablet, and every new handheld will have two screens and they will all be upgrades to the original DS. They will all be backward comparable with one another for the most part, and eventually, they will all be digital.
They are already trying to make digital seem like the more economic option with the whole idea behind Steam. I do commend them for being different with how they do it, but the idea is still the same, and the idea is still brilliant.
The Wii U wasn't copying the Wii, it was copying the more successful DS.