From what i understood, Iwata didn't mean they would the exact same architecture, just upgraded, but an architecture that allows them to use what they learn from Wii U and apply it to both the DS next an Wii U next. As in, how they could work with Wii U even if that means another type of architecture; same goals but different path.
Yeah, that's basically my idea of how next gen will pan out.
It's obvious that, even if 3rd parties release an equal version with all the extras on Wii U next, the game still won't sell a lot because the userbase just isn't on Nintendo's side and if we look at the japanese market, it's even worse: the handhelds will get the best support.
So, in Japan's case, having a system that "automatically" can play the same handheld games but with better graphics, it provides a great library for the home console.
"Even activating platform specific content for each game"
This could be a good incentive for people to buy both consoles.
Amen!
- DéliopT likes this