Iwata on Jan 30th said:

"For example, currently it requires a huge amount of effort to port Wii software to Nintendo 3DS because not only their resolutions but also the methods of software development are entirely different. The same thing happens when we try to port Nintendo 3DS software to Wii U. If the transition of software from platform to platform can be made simpler, this will help solve the problem of game shortages in the launch periods of new platforms. Also, as technological advances took place at such a dramatic rate, and we were forced to choose the best technologies for video games under cost restrictions, each time we developed a new platform, we always ended up developing a system that was completely different from its predecessor. The only exception was when we went from Nintendo GameCube to Wii. Though the controller changed completely, the actual computer and graphics chips were developed very smoothly as they were very similar to those of Nintendo GameCube, but all the other systems required ground-up effort. However, I think that we no longer need this kind of effort under the current circumstances. 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."