For those saying the PS4.5 will trump the NX, in theory, I'll propose a question:
Would you rather:
Sell/junk/give away your PS4 and get a ps4.5 that plays all the same games, some of them slightly better
OR
Get an all new system with all new games AND keep your PS4 and still be able to play 99% of PS4 games?
I know some will pick option 1, but I think a lot more would pick option 2. I think an even bigger chunk will pick option 3, though - 'keep my ps4, don't get either ps4k or the NX'
There are two scenarios for existing PS4 owners that will compete with NX:
1) They just keep their PS4 and continue gaming on their PS4 and don't need another platform. This costs them $0 in new hardware.
2) They trade in their old PS4 and buy a PS4k. Let's assume the PS4k is $400, and the trade-up value of a PS4 is $200. This would cost them $200 in new hardware.
Do you really think NX is going to be especially competitive against either of those scenarios, when Wii U wasn't despite having 1) a good library of multiplats at launch (most of which came from publishers that pledged future support if people bought the ports) alongside a first-party lineup, 2) no competing new hardware whatsoever, 3) a terrible time against PS4 and Xbox One once they launched despite both platforms being
more expensive than Wii U?
The third-party lineup will need to be astronomically better on NX, and the perceived value of Nintendo's own software will likewise need to be astronomically better than it was on Wii U, if Nintendo's going to suddenly go from failing to sell at $100+ less than the competition to selling better than the competition at a similar price point (for non-Gen 8 owners) or making them pay even more for hardware this gen than they would with any other option.
I don't think there's a magic bullet where Nintendo gets that formula exactly right to capture some unspecified number of potential PS4 owners. I think they have a better shot at capturing a completely untapped market.