Been there...
Nice article, thanks for pointing it out. One that I've had for a while is the STI Technical Description from Australia, which I found online here:
http://www.wrxhawaii.com/misc/Impreza WRX STi Technical Description.pdf
It has a lot of the same info, but in far greater detail. The problem is that it is all about the 2002 Australian STi, which obviously isn't exactly what we're getting. Still, a lot of the items are surprisingly similar, including the intercooler sizes, the clutch pressures, AVCS, etc. The Australian document just goes into more detail and has pictures and graphs. Maybe they'll get around to doing something similar for our final non-draft version.
Nice description of the sodium filled exhaust valves. The other document has pictures of them, including how they fit in the engine, but doesn't bother to explain how they're used as a heat pipe.
Another difference is that the '02 Australian STi seems to have Suretrac LSD for both front and rear, while ours comes with a clutch-type mechanical in the rear. Our document seems to imply this is a good thing (and certainly better than the viscous rear from the WRX, and thank goodness for any front LSD). We also get the trick DCCD-A.