All this talk of brake fluid changing got me in the mood so I did a vacuum bleeding (Mityvac) on my 2012 Mazda3. It has almost 84,000 miles on it and I hadn't touched the fluid. (I used to change it every 30K miles in my 89 Accord, as specified by Honda.) I've been checking the fluid with a cheap electronic moisture detector I purchased and it still read to be OK. The darkest fluid in the system was about the same color as Ardbeg Ten (for you scotch aficionados). It was about the color of honey. The full job used about 24, or so, ounces of fresh fluid. The pedal feels the same so I'm not sure there was really any benefit to doing this.
Even though my Mazda3 was assembled in Hiroshima the master cylinder and calipers all have "FoMoCo" stamped on them. I thought that was interesting.