So, here are my thoughts:
1. Personally I am superexcited since I love Nintendo and this will finally unify their software output, meaning they will no longer waste resources developing two versions of Smash Bros. Basically, Nintendo will become a more effective software developer (which will be slightly offset by the increased specs), and that in itself is exciting to me.
2. I also really like the idea of removable controllers. I actually suggested this back when the Project Cafe-rumours were rampant, on a norwegian forum before i got activated on gaf. Check it out, you probably wont be able to read it, but just look at the pictures
http://www.diskusjon.no/index.php?showtopic=1337440&p=17636929
and
http://www.diskusjon.no/index.php?showtopic=1337440&p=17642875.
The benefit with this is that you get a very flexible solution, supporting motion controls, 2d-games, 3d-games and multiplayer, which is simply a very good way to rationalise all the stuff nintendo usually want to do with their consoles, and also without the costumers having to buy a lot of new accessorizes, which was a problem for both the Wii and Wii U.
3. The thirdparty list looks really promising - but i honestly have my doubts about how many of them are fully committed outside of Sega/Capcom/Squenix.
4. I am very saddened by the loss of a d-pad.
5. They have not confirmed touch - which is mostly fine with me, but will make porting DS/3DS-games harder.
6. Graphics looks more than good enough, however, i am concerned about the battery life. The huge vents on top of the tablet means it will have to remove a lot of heat - which will use a lot of battery.
7. While I personally love it, and think it does have a clear message, I am not sure exactly who it will be able to target in this age of free games on mobile. The hook is imo nowhere near as good as with the original Wii, and the balance in the library will never be able to touch the PS4/Scorpio, meaning the Switch will once again be in a difficult middle position. Leading into...
8. The risk of this bombing. I very much agree with what you guys already have written, that Nintendo are a very interesting and important part of the console business since they are different, and the fact that they are still a plattform holder means they feel obliged to fill out their library with experimental and quirky games in addition to the blockbusters. As we saw with Sega, those will go away pretty fast if Nintendo leaves the consoles business.
So yeah, personally I am very, very excited. When it comes to Nintendos performance in the market however, I am more skeptical.