Sorry, but for me it is DS.

PS2

Good point, but I'm sure the OP is referring to this gen only.

PS3 wins it because of the PSone RPGs for it... plus some of the newer RPGs like Valkyria and Demon's Souls. On top of that it has Dragon Age =)

There's more RPGs coming out on the DS each year then there have been for all the consoles in the last 4 years combined.

Pretty much the major reason for that are companies like Atlus, Marvelous Interactive, SquareEnix, Namco and Nintendo. All of which make numerous RPGs a year for the system. Whereas the may make 1-3 for consoles a year.

If we are talking all systems, then it has to go to SNES. Way to many classics.

For me its

SNES >>> PS1 > PS2 > x360

I don't have a PS3 yet so I can't judge it.

If you haven't played a lot (or any) PS1 classic RPGs, then PS3 or PSP for sure.

Otherwise I'd go with PS2 or DS, depending on whether you preferred handheld or console.

i was going to include ps2  but i only wanted this gen stuff. 

Definetily the DS, it has such an huge amount of JRPG's, I think it's on it's way to surpass both the PS1 and PS2 in terms of sheer numbers.

If you want an mixture of WRPG's and JRPG's, then I would have to go with the PS3, not only for the RPG's that it has, but also because next year it's going to be a JRPG paradise for PS3 owners.

SNES x]