I cannot seriously convince myself that people are interested in managing anything other than their personal documents. When people say document management, what they're really interested in is communication.

People communicate to create, people create to communicate. Think about the top 3 software you use everyday. My bet is 2 of them is really for communication. Email. Weblogs. Wikis. All about communication.

With that in mind, a document management application is really a piece in the puzzle to improve communication between people. Between employees, employers to employees, companies to clients, etc.
That is the main reason why I've decided to integrate a wiki into a document management system. By making collaborative editing painless, a wiki makes persistent and publishable communication easy. A power wiki like http://www.twiki.org arguably already provides basic content/document management functionality, but there's alot alot more to be accounted for in this space that cannot be addressed by a simple wiki.

Another implication of the emphasis on communication, is really that its about bringing people closer together. Its not only about people, its about the relationships between them. But that seems highly theoretical to me, and I’m still finding a way of practically expressing that in software.