Some source code of Google Docs suggests upcoming features that could make the service better suited for storing media content. There's a audio player with playlist management will be added to the service, as well as a preview pane that'll allow you to view more information about your files and even check the content without actually opening the files.
The code contains references to "previewpane," "mediapreview-audioplayer," and "addtomediaqueue." From the looks of it, the preview pane will be able to play audio files, as well as previewing your text documents and spreadsheets.
The code also refers to "collections," which'll allow you to create a group files from multiple folders. Even more exciting, the "open with" option is the first big step toward third-party apps in Google Docs.
At the moment, Google Docs includes a small list of applications, but that will change when you'll be able to add third-party apps. That's why Google will have to add a new option for selecting the application that will open a certain file.