I know that you were limited by what you had on hand, but I'd love to see the high-res Nikons (D2x and D200) as well as Velvia 35mm in there (maybe in a carefully focused Leica, or a Canon film body with the same lens the digitals used). It looked like the "old" 1Ds came pretty close to Velvia 645, and the 1Ds Mk II at least equaled it. I bet Velvia 35 would have been completely blown away by this crowd. Another interesting addition would be a Hasselblad 500 or 501, to see how the Zeiss lenses compare.
The reputation of the D200 is that it is pretty similar in resolution to the original 1Ds , with the D2x a bit better - the newer Nikons are supposed to do a bit better per pixel than the three year old Canon. I JUST got a D200 (the first really affordable high-res body), and I can't wait to see what it can do (but we've had unbelievably dreary weather here for the past several days). I have used a lot of scanned MF film, as well as lower resolution digital, and I'm interested to see how well the D200 stacks up against 6x6 - it won't quite get there, but how close will it come?