Architecture Field in Finder Info
Did this sneak in with 10.4.3, or has this been around for a bit longer? Take a look at the screenshot:
I guess this is a good thing, though I was a bit suprised to see it visible at this stage.

Architecture Field in Finder Info
Posted Nov 11, 2005 — 7 comments below
Posted Nov 11, 2005 — 7 comments below
Steve — Nov 11, 05 531
Brian Christensen — Nov 11, 05 532
Jesper — Nov 11, 05 534
Mike K. — Nov 11, 05 536
Carl — Nov 11, 05 537
Uli Kusterer — Nov 13, 05 542
thoran — Nov 19, 05 554
Of course the Workspace is NKA (Now Known As) the Finder, and the inspector is combined into the viewer window whereas previously it was in a separate window.
This was 1993. And if you poke around the Mach headers from back then, you'll find reference to numerous architectures.