great chart.
5th gen started exactly when 3rd ended.
6th gen started exactly when 4th ended.
7th gen started exactly when 5th ended.
8th gen started exactly when 6th ended.
according to chart, 7th gen is ending this year, so 9th gen is starting also this year, and would keep the pattern of the chart. So, Seems NX is 9th gen.
But NX successor should be also 9th gen.

It depends on when the PS5 is out, and how long Nintendo supports it after that (and if they will release an updated NX eventually). But the fact people are discussing whether the NX is 8th or 9th generation is a sign that the NX will be out way too early.

There is no argument as far as facts go, it's ninth generation. People who argue it isn't do not understand the classification of generations.

By that reasoning, Dreamcast was a 5th gen system against the N64 and PS1, as for most of its life, it was up against those platforms.

I really don't see why the length of the Wii/PS3/360 primacy should mean the 9th gen is going to be delayed further. On the other hand, the pattern of generations starting around the time that the generation two prior to it ended has endured through everything... so why should it change now?

Incidentally, there's really no reason to think that the XBT and PS5 will be released as late as 2020, right now. It's based on the assumption that this generation will go somewhere near as long as the last one did, despite the last generation being a far stronger generation in terms of sales of all platforms. The general pattern is a 5 year gap between generations. This would see the next systems coming out in 2018, which is right about where we'd expect it to happen, if the only thing that happens with the rumoured "upgrades" is a resolution increase.

And if I'm right, and the NX (console) doesn't release until 2017, then there'll be a 1 year gap. But even if it's a 3 year gap, that really doesn't mean much on its own. The Wii U was in the same generation as the XBO and PS4. The NX is the successor of the Wii U. Therefore, the NX is 9th gen. If both Sony and MS wait until around the time that NX is being replaced by its successor to release their successors, then they will have kept the same systems for both the 8th and 9th generation of consoles. Because that's how generations work.

That could happen, in the third generation Atari had both the Atari 7800 and Atari XEGS counting towards that generations.
And the Sega 32X Sega Saturn are both part of the Fifth generation.

The NX will be the first console in the 9th Generation, it doesn't have to be the only nintendo console.

NX 9th

PS4.5 8th

XB1.5 8th

You are correct sir. This would be the way it goes into history.

7th gen was as long as it was cause we hit 28nm wall.

TSMC has announced 7nm for 2017...now, they are pretty much Peter Molyneux of semiconductor industry, but if some minor miracle happens and they (or GloFo) actually have it by late 2017/early 2018, then there is a theoretical chance for PS5/NextBox in 2018.

Personally, I highly doubt it, more like 2019 - especially if both MS and Sony decide to go with Navi architecture (slated for 2018) and keep the price in $400 range.

Pretty much this.  Defining consoles by their 'generation' is probably going to die.  You'll have NX in Gen 9 all by itself for 3+ years? Are people going to lump PS4 Neo and whatever the hell MS releases in response into Gen 9?  When the successor to NX comes out will they put it in Gen 10 meanwhile SONY and MS finally are releasing their 'Gen 9' consoles?

Gens just don't fit anymore.

Wii u was 8th gen, it failed so Nintendo had to Rush their 9th gen console. It's very simple the way I see it