New standards for communicating metadata, such as XML, do nothing to
address the underlying issue of where it originates. Controlled
vocabularies and relatively static ontologies are not solid foundations
for information systems that must cover a wide range of subjects,
support rapid integration of new information, be easy for the general
population to use, and can only be maintained at moderate expense.
Large-scale use of metadata requires new answers to fundamental
questions.
"Hydra-Headed Metadata" by
Jamie Callan,
W. Bruce Croft,
Eduard Hovy.
http://www.dgrc.org/dg-online/december01/metadata/metadatafinal.pdf