Has anyone tried Castanet, Flamenco's algorithm for generating hierarchical
faceted metadata?

"Castanet is an algorithm for (semi)automatically generating hierarchical
faceted metadata from textual descriptions of items, to be incorporated into
browsing and navigation interfaces for large information collections, for
systems like Flamenco.

Castanet carves out a structure from the WordNet lexical hierarchy, with the
goal of building facets that reflect the contents of the target information
collection; moderate manual modifications improve the outcome.

The algorithm is simple yet effective: a study conducted with 34 information
architects found that Castanet achieves higher quality results than other
automated category creation algorithms, and 85% of the study participants
said they would like to use the system for their work."

They have a demo showing it used on biomedical journal titles (pushed into
the Flamenco interface)