Whoever has subscribed to the "Fusion" idea, pretty much takes this as a given.
Whatever the next card format that'll be used by the NX handheld, will be used for the home version. The only reason Nintendo ever got in the disc business in the first place was cost/space issue, and it seems the time is ripe to ditch optical drives for Ninty's next gen hw. Again - for Nintendo the HH/HC gap is closing, with the NX HH making a big jump (due mobile tech advancements) and the NX home version will inch forward, not too different from GC-Wii.
The only question is the size of these game cards, IMO as low as 32 and high as 64 gb.