digital imaging = visual information?

In another life, an improvisation coach told me that acting was communicating and therefore all should study it. Through acting you learned to express the feelings that you wished to communicate to another. So too, imaging expresses information. When calling an image visual information the question is what is the information it is expressing. Is it a surrogate, a representation of something else and thus relates all the information of the original or is it itself an original. This differentiation has long created a dichotomy for those creating digital image collections.
There are those creating libraries of surrogates, they may be surrogates of objects in real collections or used as teaching points. These libraries are the ones that talk about increased access for many, preservation by reducing handling of the original objects, and improved presentation methods.
Then there are the ones who need improved filing systems to retrieve the right digital file. They talk about reuse. The image itself has a provenance if you will. In the past I had grouped my marketing clients here, but now I see that both my institutional and corporate clients have both such collections. The corporation advertisements are in some ways surrogates for its product which might be seen as its collection. The institution create historical/promotional documentation of its activities whose images are important for the information that they contain. I am just about to co-chair a panel at the MCN annual conference entitled"the DAM - the Many Headed Hydra" where we will discuss this same issue, how do we manage these two different types of collections?