At this point we will know everything about the console before Nintenedo even announces it lol
Except what games are being made for it.;_;
As others have said thought these changes make a lot of sense if they want to have two detachable controllers for stuff like Mario,Smash,etc.
Really it all comes down to how these buttons feel to use and Nintendo is usually very good about that.
The most interesting thing IMO is that Nintendo do has often seemed reluctant to appear to be copying other companies which clashes with this. Maybe they'll design more in line with their competitors in other aspects.