Regarding Schumpeter, it seems to me that there is a basic issue 
underlying most of this discussion, including Solow's criticism of 
Schumpeter and the concept of obsolescence in relation to creative 
destruction. One can describe this in terms of the notion that there are 
two classes of economists.

First, there are those who look at the economic world (economic growth, 
economic fluctuations) in terms of mechanical forces, many of which 
remain to be discovered by mining the data sets. This view was bolstered 
by the macroeconomics boom of the 1950s and 1960s, which incorporated 
the fledgling methods of econometrics and mathematical modeling. 
Obsolescence, from this point of view, is an event that occurs as time 
passes through the operation of the mechanical forces.

Second. there are those who look at the economic world in terms of 
distinctly human action. In this view, it is not mechanical forces, but 
human entrepreneurship that causes the economic world to be what it is 
and to change. The newest of the new growth theory, for example, sees 
growth as the consequence of human capital, which distinctly human 
actors produce under particular institutional conditions. Obsolescence, 
in this view, is due to the invention and innovation of entrepreneurship.

I am not well read on Schumpeter. But all of the things that I have read 
by him suggest that he saw the economic world as being 
entrepreneurship-driven. Surely this is true of his concept of creative 
destruction. The paradox, of course, is his far-fetched prediction that 
entrepreneurship would ultimately become routine enough to be capable of 
surviving a turn toward socialism.

Pat Gunning