About the XBOX exporter : despite its reasonable price, despite the cost of $99 to be a developer at Microsoft, despite the huge XBOX360 market when it was released, we did not make a lot of sales.
It will only be worse with a $1000 SDK for a less-popular console.
If all we want is labels to put on the frontpage, the Wii-U object is enough for this (with an asterisk, as Scirra does on their labels).
So I really do not know. But yes, we are only talking about a wrapper, it should not be that difficult to make in fact.
Waiting for Nintendo to contact me about Nintendo Web Framework.