Hi,
As Ada points out at the end of her post, in the upcoming release (announced last week) will have what we call "Generic XMP File Handling". This means all media formats will now be supported*.
Important asterisk note here however. What this really means is Adobe apps can now WRITE metadata to these formats that haven't had previous metadata support. You can log temporal metadata (markers) as well as add static metadata. But this new generic support does not read any metadata from those formats.
A little background. Adobe has written what we call Smart XMP Handlers for those formats already supported prior to this release. Smart XMP Handlers are capable of reading metadata from the format and adding that into the XMP format that our apps understand. We can also write metadata to XMP with the old smart handlers. What's different for those formats which don't have Smart Handlers (those formats that will rely on the new Generic XMP support) is they don't attempt to read native camera format metadata. They only allow you to add new metadata.
Hope this helps!
Thanks,
Michael