We agree, this is somewhat confusing... In fact any type of content can be stored in MediaMosa, but the current workflow expects and handles only media, like audio and video, well from the aspect of analyze, creating stills and supporting transcodings.
For example, when I upload an .pdf file, the file is stored and I can put metadata to it, but there is no support for 'transcoding' this document into another type. So by stating in the Technology Scout project that support for other content is not yet implemented we mean that full support, like we have in the case of video, is not there. In order to facilitate this properly, we need to extent the workflow mechanism to support multiple workflows for multiple types of content.