do you think OEM armrest on future cars will fit?
 

Do you think, in the future when the newer models of the FRS/BRZ equip with an OEM armrest, we, the first generation buyers can just simple buy the parts and have it installed? or do you think they'll change the center cup holder area completely?

Yes they do this on many turd sub compact cars, you buy the arm rest as a dealer option.

Ok then i'm waiting for OEM armrest rather than buying the armrests that some people make and sell on this forum. I don't like the idea of armrest make the cup holders unuseable.