Now of course by 10.0 the finder was a Carbon application, written from scratch AFAIK. But the "Workspace Manager" in Mac OS X DP1 was a rip-off from Rhapsody - Cocoa-based. Did Mac OS X DP2 use a Carbon Finder, or was it DP3 or DP4 or did it wait all the way till Beta? From what it looks like here:
GUIdebook > Screenshots > Mac OS X DP 2 The Finder in DP2 was referred to as both Finder and Workspace Manager, and had characteristics of both Finders. It looked like the Finder from OS 9 in the bottom, with a collapsable list view, icons in List view, Column View having icons, and OS 9-style sort headers, but it has that big huge icon tree up top.