i've never called it the JPRG console of this generation, nor have i heard anyone say that.
I have heard that the 360 has a good library of JPRGS and WRPGS.
It's just got a good image now with Namco support, Square Enix support, and Mistwalker support providing a good amount of JPRGS.
But at the moment, if you want to play some JPRGS on a console, why wouldn't you go for a 360?
Perhaps next year it will be different.