PdotMichael
Banned
The comment you're quoting was about the unification of the hardware divisions, not specifically about the NX itself. Iwata also said this regarding the model that their next system would follow.
Of course, an actual shared library hasn't been confirmed either, but I don't think that just "easy porting" would really improve things if they really still had to handle the porting process by themselves and submit them as different games. Many developers probably just wouldn't bother. And what you suggest there as far as flagships go would just keep the same situation they've got going to a large point, especially if their biggest efforts were limited to a single platform.
Context is important. Nintendo's handhelds and consoles were way more differently than Sony's system example. The PSP was so close to the PS2 that it got ports and spin-offs of PS2 titles all the time even till the point that people complained that the PSP is just a machine to play console games just in worse quality. The same with the PSVITA.