Metadata is one of the most useful tools we have, if we have the tools to use it! Aside from the obvious problems when no metadata is gathered during the shoot, or insufficient metadata is gathered, other issues arise because there are not always tools in the production chain that use the metadata that has been gathered!
A recent student film was used as a template by the Entertainment Technology Center at USC with the purpose of realizing the long-hoped for promise of production metadata, with some fairly ambitious goals.
The results are interesting and important, particularly considering that this is what I would categorize as Technical metadata, rather than Content metadata.