We don't have nearly enough info to make a judgment on how it will play as a controller.
But as someone who has been banging on about industrial design for Nintendo products for the past 5 years, I am delighted with what I see here. The Wii U tablet was a Fisher-Price looking toy that did not in any way resemble expensive modern technology and wasn't something you'd want to leave out on your coffee table. I had multiple friends dismiss it on sight, including my sister who's a fucking Montessori teacher!
This, on the other hand, looks slick, sleek and expensive. It looks like something a non-gamer could be excited to buy and use. It looks like something that a child who's only experience of gaming has been phones and tablets could quickly come to terms with, and would look 'normal' to his eyes.
That stuff is important, and it looks like they've got that right.
Now we just need to trust that the actual controls aren't a clusterfuck, but it would go against every fibre of Nintendo's being if they were.
My HUGE issue with this? That the console will have another super-expensive controller, and few third party games. If this was the handheld I'd be far more excited.
Also feeling pretty good that my initial reaction to the first leak was 'real' was justified.