While proposed enclosures syntax allows one to reference rich media content in various formats, it has a very limited means of controlling presentation.
For better presentation control, some additional mechanism should be used in addition to this proposal. For example, Synchronized Multimedia Integration Language[15], which allows authors to write interactive multimedia presentations, describe the temporal behavior of a multimedia presentation, associate hyperlinks with media objects, and describe the layout of the presentation on a screen. We suggest attaching an SMIL document as one of the enclosures, referencing other enclosures via their Content-IDs.
Another approach would be to extend enclosure elements introduced in this document with additional properties containing additional metadata.
RSS 2.0 enclosure elements could be extended with additional attributes and sub-elements, provided such attributes and sub-elements are defined in separate XML namespace.
RSS 1.0 enclosure elements could be extended with additional properties, provided such properties are defined in separate XML namespace.