Nintendo is the only one amongst them who has any real incentive to skip out on the generation game. As the masters of their Blue Ocean, they have about 8 more years of dominance assured to them even if they don't release a successor to the Wii, thanks to the wonders of the only kind of brand loyalty that counts: pioneer brand loyalty.
However, I don't think Nintendo is going to bank on that too much. The moment the Blue Ocean turns Red, they'll be ready to defend, and when that's no longer viable, to conquer with a new Blue Ocean. I also doubt they're going to play the incremental upgrade game again, even to their new values. The next Nintendo system is not going to be the "Wii 2", almost assuredly, unless Satoru Iwata randomly decides he was talking out of his arse for the last 2 years.
As for MS and Sony, they're both wildcards since neither one relies on the console industry to survive. Sony could decide to exit it tomorrow and still have made a net profit off of the PlayStation brand. Microsoft doesn't have that luxury, of course, as they've lost around $6 billion on the XBOX brand.
The questions are these, then: Will MS cut their losses and quit or lug it out until they at least break even? Will Sony decide they should risk another generation or will they back out? Each scenario has its pros and cons for each company, and neither one is in dire need of their games business to survive. Nintendo is an assured continued contender for as long as they can manage it, but these two are not.
Sky Render - Sanity is for the weak.
