The 2005 ILTA staffing survey says the KM cup is half-full only. 

In 49% of 500+ lawyer firms, no one manages KM. Will the cup fill over time? We’ll know more if ILTA keeps asking this question. I’ll also have more to say soon about the evolving role of KM and what this result might mean.

The survey includes about 2/3 of all 500+ lawyers. 38 500+ lawyer firms responded; the 2004 AmLaw 100 lists 62 firms of that size. So I think the data are quite reliable.