I'd take a huge univentive, yet risky move of naming it ''N64'' internally refer to it as the N64k or N64'000 and then advertise it as the ''new N64''

Reason being that its the only Nintendo system to resonate with the mainstream yet not be reliant on a childish image or family specifc audience. NES and SNES did the same but those titles sound dated to me. Nintendo alone would be decent but I still think Nintendo's name carries some negative childish connotations for many audience. N64 is rich with nostalgia whilst also sounding like a modern tech device

tell me what you'd name it :)

Wii W?

You know, to make it as confusing as possible.

Depends of the kind of system the machine is. If it's a hybrid between handheld and home console, the name Fusion is great (and it's been circulating in the web for years).

When I hear fusion I just think of Gillet  lol

So Nintendo Fusion or just Fusion?

 But why did you skip 8?

Nintendo Infinity.

I guessed the next Xbox would be called Infinity way back in like 2008 but M$ wouldn't listen. Now Nintendo has to use the name.

Wii Know What You Did Last Summer.

Nah, I don't know, Fusion sounds okay but to me it doesn't ring like a Nintendo name, it sounds a bit too tech-inspired somehow.
Nintendo Double? Nintendo Evolution? I dunno, really.

Wii We. :P Trolling aside. Maybe something more descriptive of the technology. I like how they name their Handhelds NDS (Nintendo Dual Screen) or 3DS (Three dimensional Nintendo Dual Screens.) I think the Wii brand should be dropped though. It is too confusing as it is. And Nintendo should always be in the name so that it has the brand recognition.

And 7??

NES, SNES, N64, GCN, Wii, WiiU.

NSFW

Nintendo Super Fusion Wii!

But I like Super Fusion on its own.