Notes

He's under strict NDA with Nintendo Japan
Informations are from march 2015, with some updates from june-july
He received a bunch of patents (some of them are publics now), info about what Nintendo is planning and a list of games potentially in development (some of them may or may not have been cancelled), third parties included
NX is a platform, not tied with a single device
Wii U is still in the picture thanks to good software results for games like Splatoon, will still be the main home console in 2016
3DS is a bit old, they're planning of replacing it. Some games will still come out on it, but big projects are being moved on portable NX
With NX, Nintendo wants to create a platform where they can develop software for multiple devices with ease, from the home console to the portable to smartphone and tablets. They'll have a big catalogue available for multiple platforms, with cross buy, cross saves and cross play, similar to what Microsoft is doing with Xbox One and PC thanks to Windows 10 (that allows to play many Xbox games on PC, which is also getting a bunch of ports from Xbone). Each platform will still have exclusive games
NNID is tied to the single device, but it will allow to share details between platforms, like friend list, contents, local coop games, etc. Thanks to the new membership program (the successor of Club Nintendo), we'll benefit from the new Nintendo policies in terms of rewards
They'll show the portable in spring 2016, will be out for the end of the year or spring 2017 max. Specs will be higher than PS Vita but nothing mindblowing, screen resolution should be 540p, considering 720p if costs go down. BC with 3DS was problematic
Wii U successor will not have an optical drive, which will be optional. It will sync with the portable (not obligatory). Specs won't be super high, but close to PS4/X1 (doesn't know how much, like with the portable this is still subject to change anyway). Cross games will look better on the home
Nintendo is focusing a lot on the anti-piracy system
Big focus on the OS as well. They hired people that worked for Google on Android, the guys who worked on the Gamecube OS and Wii U browser are there too. Optimized versions of the same OS for every NX platform (think, again, W10), each with its set of specific functions. Updates will come out at the same time, they're focusing on making the OS blazing fast on every platform
The home console can connect with the portable to send to it its own version of the games you buy, will use the same tech as the Wii U-Wii U Gamepad streaming to do that, or the internet connection
The home will have bc with the Wii U. Gamepad should be compatible as a controller, considering selling it standalone. Can connect with the portable for offtv and bc. WiiMote compatibility is being considered too. As for support, since the new home won't have an optical drive, they're considering an external one. Also being considered NNID/eShop bc for titles bought on the eShop. Seems they're considering digital games sharing too, but this bit is not perfectly clear
The portable will have its own internal memory, which will be expandable
There will be a complete overhaul of online infrastructures, but Nintendo is determined to hold successful operations as Miiverse, extending it even further and making it a central hub for communications by developers and a meeting place for players. It will be even more interactive with the ability to upload videos and screenshots in an integrated system and not dependent on the game
Voice chat and interactions between users will be revisited too, much will depend on the users age though, to protect the minors
The home will be out 6-12 months after the portable, creating the "NX system" that will allow Nintendo to better use their resources in games development
They approached third parties during E3. Capcom, Square-Enix, Ubisoft and Electronic Arts already have devkits. Dragon Quest, Final Fantasy, Sonic, F-Zero and Metroid are in development, doesn't know if these are main episodes or spin offs. Zelda is currently a Wii U only title due to high development costs, but they can reconsider to have another big game at NX launch
Prices will be low, 200-300€ (for the home?), considering a bundle with both for no more than 500€
Many of these things will be discussed in future Nintendo Directs, which will have a different host in every market if Nintendo can't find a new CEO by october
A new 3D Mario will be shown, along with a new Zelda trailer. Retro moved their project on NX, will not be unveiled before 10-18 months
They'll talk about a new "Club Nintendo", which will be in full function with NX
Considering making agreements with phone carriers in order to better manage applications like Miiverse, Club Nintendo and the ability to purchase software by phone. Some of these will be out by March 2016
Is everything set yet? Yes, but with Nintendo you'll never know. If he has updates he will share them with us.