I would like to see Confluence track and maintain versions of attachments much like it currently maintains versions of the page itself.

Use Case:
When using Confluence as a software project tool, we attach requirements documents, specification documents, example data files, prototype screenshots, etc...
During the design phase these documents are going to change regularly.
Some of the time it is necessary to retrieve older versions of the documents to figure out why a certain decision was made. Sometimes you'll need to go back to an earlier version of the document because a design change means you need to rollback and use older specs, prototypes, etc.