I am relatively new to the MediaWiki and Semantic MediaWiki field having come from Model Driven Architecture  and recently from a project to add Semantic Web RDF structure to the HL7 FHIR electronic health record standard .
During the work on electronic health records, a Semantic Web tool Protégé was used and the discovery of persisting information in triple stores was appreciated along with the ontology mechanism for controlling it. However the mechanisms for user interface design and multi user support were missing and in the search Semantic MediaWiki was discovered.
Edmond Scientific Company has installed two instances of MediaWiki with SMW one as a sandbox and the other for production. The application is for internal application portfolio management covering infrastructure assets and programs under development.
Work is progressing in assessing ontologies for system portfolio management including architecture, program oversight, infrastructure, security and risk management. These ontologies are the analysis starting points for SMW implementation.
SMW has also been used for Enterprise Architecture of a system portfolio for a customer.
Recently the health record example was migrated to SMW as a proof of concept.