I wouldn't be surprised if PS4 sells well out of the gate initially, like I said I think "you can't have this" is a funny psychological tool to some consumers, I think some Japanese gamers will latch onto that and it creates a kind of artificial demand early on by having the Japanese launch last when Japan is generally used to getting things first.
That said, I just don't see the content long term. Japanese devs can barely make PS3 level HD games and release them on time/budget ... PS4 is going to be even more difficult for many of them.
It'll get the staple FF/Kingdom Hearts/MGS/Resi Evil franchises, but even these will probably take a while to finish up and 90%+ of the content on the PS4/XB1 is going to be Western games. I just think that's a reality of the situation.
It's not 1999 any more, even though it's a nice pipe dream to entertain. Sony has also sold out their own Japanese studios too, there's the odd game that comes from Japan, but overwhelmingly its clear that their main PS3/PS4 development has shifted to Western studios and Western tastes.