The D2 comes with the best screen protector installed - it's called Gorilla Glass.
I dropped my D1 purchased last November about 10 times, almost all on concrete and asphalt.
Zero scratches, nicks, dings...nada....nuthin on the screen. Now the metal case was another thing - lots of dings and scratches and dents, but the screen - perfecto.
Partly due to the Droid design where the screen is just slightly recessed below the edge of the case around it, and mostly due to the amazing Gorilla Glass.
D1/D2 are the first phones I've ever had w/out a screen protector, and never will use one on them.