Xenoblade has the best environments in any game ever.
Yes I've played Just Cause, Oblivion, all Final Fantasies, SotC, Okami, all Zeldas, etc etc.
As long as polygon count and screen resolution isn't a big factor to you(it shouldn't be), Xenoblade beats everything.
EDIT: It's also worth mentioning that the environments are 100% interactive. There are no invisible walls preventing you from jumping over waist-high fences. Kind of a big deal in a JRPG.
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