Repurposed from a dm-discuss post.
Let me be a little contrarian and argue first (as head of the Metadata Management Office at a Fortune 100 company, and the manager of a modern MOF-based metadata repository) that
the terms "metadata" and "repository" are quite useless and need to be left behind.
Really, what we have is the overall functional area of IT or IS (take your pick). This general organization capability, just like its counterparts in Finance or HR or Manufacturing, has processes and data elements it needs to manage. It manages the definition of data, process and function models, the physical data and software artifacts implementing them, hardware computing platforms supporting those artifacts, and a host of process-oriented abstractions: change and incident tickets, work orders, services and systems as cooperatively defined with the client, and much more. It also manages the human and financial resources necessary to support the IT capability.
If this seems misguided, consider the following questions:
The definition of an "entity" would generally be accepted as "metadata." Is the name of the analyst who defined that entity metadata? Many tools can and do store it. What about the project in which the model was created? What about the financials underlying that project? The software quality practices? Were inspections carried out on the data model?
A logical evolutionary step for metadata repositories was to extend their data dictionaries to include the programs that accessed the various data elements. But are the change tickets that put those programs into production metadata? Are incident tickets related to those programs metadata? The headcount and budget required to maintain the system in production ongoing?
If you say no to my questions, then I have to ask: where is the ROI on your product? I can tell you what my clients are asking for: an integrated picture of the IT environment, with complete transparency and traceability across those questions I'm asking.
You can see the problems quite clearly in the CWM, which has "Email" and "Telephone" as metamodel entities, which has been controversial on the dm-discuss list. I support the pragmatic argument that IT assets are created by people we might want to reach, and therefore their contact information belongs with the asset metadata -- but the results do seem curious, as contact information becomes both metadata and data -- it "crosses levels." Hence my argument that it's all really just "ERP for IT."