Abraham Bernstein’s Google lecture Making the Semantic Web Accessible to the Casual User (2008) is quite good.
Relevant to topic mappers are his comments on structuration theory and how social structures both make signals meaningful as well as limit what meanings we will see. Topic maps can capture the meaning as seen by multiple parties as well as anyone who can see separate meanings as being attached to the same subject.
An “interactive” search interface tested by Berstein and his group got the highest rating from users. Making users into collaborators in authoring topic maps, asking “Did you mean?,” sort of questions and capturing the results might help capture unanticipated (by some authors) answers as well as increasing user satisfaction.