Generations are becoming an irrelevant term in regard to consoles. If you insist, Neo is in the same boat as the regular PS4 model though, unless at some point it receives something eclusive.

The Neo is 8th gen whilst the NX is 9th, like several others have already said. However as we're moving towards a time of incremental improvements and upgrades to consoles as opposed to entirely new systems, gens will grow more and more indistinguishable so it wouldn't surprise me if eventually the entire notion is abandoned.

Not for now, though.

We know nothing about either but in the spirit of discussion.....

PS4K is still 8th. Nx will be defined as 9th by everyone who isn't Nintendo.

PS4=PS  neo

XB1=XB1.5

WiiU != NX

The NX isn't just competing with the Neo or XB1. That is just not correct in any way imaginable. Once the NX comes out. And say it sells  10M in its first year. And say both the Neo and XB1.5 also sell 10M in that time. Publishers aren't going to look at them and go; "Ok. they all have 10M consoles out there " nope. Publishers will look at them and go. "ok, there are 70M PS4s, 45M XB1s and 10M NXs"

Cancelled the wiiU after launch? The wiiU was a complete failure in every sense of the word. And will be on the market longer than even the ogXB was on the market. Yet I don't see anyone saying MS "cancelled" the ogXB. Nintendo released an 8th gen console. They are now releasing a mid gen console. that may or may not be described as 8th gen (for simplicity sake) but is in actuality 9th gen unless we want to say they made two completely different platforms in the 8th gen. 

To cancel something immediately after launch would be like they release it in 2012 then in 2013 they say they are making a new console to come out in 2014. the NX comes out in 2017. that's a good 4-5yrs after the wiiU was released. 

NX: 8.5

PS4Neo and XBOne1.5: 8.1

This. Not sure this even needed to be addressed

impossiblet to say at this point. The PS4Neo is obviously just an upgrade essentially and part of the current gen. The NX however we have no room to say yet.

if the NX is considerably more advanced in some technological way than the current systems (whether in application OR tech) then obviously it will probably be its own new generation.

if the NX spec wise is similar to PS4/Xone then I think its safe to say that its not really a new gen

If the news hasn't hit you yet, NX and PS4K are pretty much evidence that there are no gens anymore and we should stop with that outdated nonsense.

thats not really how it works, it will be replaced in March 2017.