Not sure about anyone else, but I actually do not have a problem with the button layout.
It seems just fine to me.
But like I said earlier, the design is pretty similar to the Xbox 360 controller and it may get a bit confusing for some to switch over from 360 to Wii U and use that controller.
The contoller will feel similar to your Xbox 360 controller and even has the same button(a,b,x,y) and for games that have QTEs it will become weird trying to press those buttons since you may actually forget that you are playing with a controller that feels like a Xbox 360 controller but has a completely different layout and may end up pressing x or y when you really meant to press a or b.
But for someone who isn't so used to the 360 controller it will be just fine.
I will get used to it if I ever get one.