iPhoto Metadata – Bug?
Maybe it's not a problem with differing standards support at all - maybe it's just a bug.
I have two photos, I've called them "goodmeta.jpg" and "badmeta.jpg". They both have keywords, but the keywords only survive the trip into iPhoto for one of them ("goodmeta.jpg").
Here's the metadata for goodmeta, and the metadata for badmeta.
The actual keywords are in the same place in both - in the XMP data - but the badmeta file doesn't have some of the other metadata, so I guess iPhoto is just skipping metadata import, ignoring the metadata that is there.
I was hoping I could write a tool that would pick up the metadata from where iPhoto isn't looking and drop it where it is, but it seems I'd have to make up something for the missing metadata to get iPhoto to consider it. At this point it's probably better to just report it as an iPhoto bug and hope they fix it.