I've been thinking about leveraging git-annex for a workgroup document repository and I have just watched your views demo. The timing of the demo is great because I need to deploy a document repository with per-document metadata and your views concept seems like a great mechanism for associating metadata to documents and for displaying that metadata.
While I don't expect to use your views concept for my workgroup repostory, a later iteration might do.
The metadata in my use case begins with all the weird metadata seen on a book's copyright page. In addition, per-document provenance, like how one found the document and (if we're lucky) a URL where the latest version of the document may be found. Metadata values may be simple strings or may be markdown text.
So, are you considering a metadata syntax that can support complex metadata? One example is multiple authors. Another issue is complex metadata values, like key=abstract and value="markdown text...".
