Although the layout, size and function is very similar to the N80, look at the details and you'll see that the actual pieces are different. The large mode select knob is different, the body is different in every detail. I agree that it is much more accurate to say it's based on the N80 than the F100.
In the same light, I've seen many references to the D1 as being based on the F5. As you noted, it's much closer to the F100 and shares much of the physical layout and actual controls. It has RGB metering, but doesn't have a removable finder - one of the inherent characteristics of the pro F bodies. In the same way that the Fuji S2 is built using an actual N80 body as the foundation, Kodak has made digital bodies that are modified F5 bodies. Nikon hasn't. The D1 is really it's own camera even with a few shared part and the D100 is even more so since it has very few actual shared parts that (at least externally) are visible.
Hot on the heels of the Nikon release, Canon ups the ante with the D60. Canon has loaded this new camera with a lot of improvements over the D30. This is great news in that the more options out there, the more pressure it puts on pricing. I'm not very enthusiastic about the D100's 1.5x crop ratio, so the price will need to be quite affordable for me to invest in a stepping stone to a future full frame camera.