Photo meta data editor for OS X? I'm looking for software that will let me do bulk edits on metadata for photos in my iPhoto library. Specifically I'd like to be able to edit the date on the photos and the location information.

I'm going to be adjusting large numbers of photos so batch operations are an absolute must for me. Bonus points if I can copy and paste meta data information from one photo to many other photos. And it would be especially helpful if I could copy just specific meta data fields, not all the data or none of the data.

I've already tried to do some of this stuff in iPhoto and some of it is possible, but not great, and some of it is impossible. For example: I can edit the location meta data on photos but the UI for doing so is kind of awkward and slow, though it does support batch editing. I cannot edit the date and time stamp on photos though. That's one field I'd really like to edit (because the camera had the wrong date and time on them when some of these photos were taken).

So I'm looking for non-iPhoto suggestions here.
You can edit Date and Time in iPhoto, and do it in batches too: Photos Menu -> Adjust Date and Time - and it will also correct the date and time on the original file if you choose to.

Another thing to consider: iPhoto catalogues the images on import. If you subsequently change the metadata with a 3rd party App, iPhoto won't recognise this. It will not rescan for changed metadata, so while you're original files may be corrected, it'll make no difference in iPhoto.