What's the story with VBA and VSTO customisations?

For development, will we be able to store the xml and VBA inside it in plain text, so we can easily use source-code control, merging changes etc?

For production, will we be able to protect the file, such that the VBA code can't be viewed?

Will we be able to store VSTO assemblies in the file, so they can be distributed much more easily than at present?

Will I be able to digitally sign parts of the xml file, use DRM on bits of it etc?