I'm not a pessimistic troll or something but I can pretty much confirm this is fake.
Realistically speaking, this is too good to be true. You cant honestly expect ALL of this in one update. That's way too much of what has been asked for to be a real update.
I dunno, it kinda seems like Nintendo is finally learning and listening. The fact that the online service was delayed from last year to this year, and seemingly again to later this year, leads me to think that they're at least considering and experimenting with the things that fans have been clamoring for, such as voice chat built right into the system, despite their initial plans to only limit it to our smartphones. Other things seem incredibly likely to come eventually: rearranging the layout of our titles, the ability to create folders, more media apps coming, and the ability to get more themes. None of that stuff seems unlikely to come to UI soon, so I'm really not seeing anything that's really convincing me that this isn't real. I'm skeptical, but I'm leaning much more towards it being genuine.