Satoru Iwata announced that Nintendo's next generation of consoles won't be as different from each other as they have been in the past. They're working on a "similar" handheld and console that are cross compatible, taking inspiration from Apple's iOS and Google's Android platforms.
Iwata may have been indirectly verifying the Fusion DS and Terminal rumor. The two systems do share a few striking similarities in the hardware department and even the ability for the Fusion Terminal to charge the Fusion DS. Still, a rumor is still just a rumor until it's been either confirmed or denied.
Nintendo restructured its R&D department last year and merged their handheld and console teams together and looks to take advantage of what they managed to accomplish with the Wii U, according to Iwata:
“In this perspective, while we are only going to be able to start this with the next system, it will become important for us to accurately take advantage of what we have done with the Wii U architecture. It of course does not mean that we are going to use exactly the same architecture as Wii U, but we are going to create a system that can absorb the Wii U architecture adequately. When this happens, home consoles and handheld devices will no longer be completely different, and they will become like brothers in a family of systems.”
That's fine and well, but one thing Nintendo definitely doesn't want to do is force every game to be made available on both platforms. That might work for Virtual Console titles since most devices these days should have no problem handling an NES or SNES game, but it could potentially be detrimental to third party support. Unless the two systems are identical in hardware, console releases could be held back by the limitations of the handheld.
Iwata does admit that he doesn't know if the hardware configurations will be integrated between the two systems. Contrary to that, the number of different configurations might increase.