I noticed with the 8 Dec nightly that
1. the uploader is a generic file uploader rather than just images (good!)
2. Seems I can use it to upload any file (.mp3, .doc, .pdf as well as images)
I think this is excellent (never really understood the file limitations) so three cheers to the devs... just need to delete the "Upload File Types" WPMU admin function now.
Is all the above about right?