Went to the downtown Nashville dealership today (they're always great, props to them) to investigate the 2012s.
I was able to find the same line in the print marketing:
And look at this:
Too bad that's on the MAXIMA!
Here is the Z, and it's the same for all variants (base/sport/MT/auto):
So despite the literature, sadly,
there is no brake ducting on 2012 370Zs.