Eric Drexler has responded to my last reply. Let me focus on one key issue. I wrote: The main argument you gave for why a nanotech revolution could happen suddenly is that new nanotech designs could “unfold at the speed of new digital media”, i.e., we could sent such designs around fast as digital files. But if this were all that was needed for a technology to improve rapidly we should now see rapid gains in the design of novels, music, and software.