Even if the Driod has the same resolution screen as the Nexus One, it is simply more logical to compare the iPhone 3GS to the Nexus One since they have a similar form factor. I made this image simulation for an easier understanding of the Nexus One screen space over the iPhone's.
It is amazing how you could fit two and a half iPhone home screens. The new iPhone better have a similar screen resolution in order to compete, and let's not go into the AMOLED thing.
Click on the next image to see how beautiful 480x800 is. It must look pretty sharp on real device size.