Dave is a self-described “proud curmudgeon and pragmatic cynic” and the founder and chief scientific officer of Cognitive Edge. I think without any doubt, he is the most influential thought-leader in the KM world.
He has had a massive influence on me and whenever I am struggling with an issue - I think to myself "What would Dave's views be on this?"
I will often google the issue and find he has some very strong opinions on the subject in question.
I don't always agree with him but he really causes me to think deeply about the topic.
Whether you are familiar with his thinking or not go take a look at this profile of Dave's work
David Snowden: Profiles in Knowledge
recently created by Stan Garfield. A lot of interesting material.