Overview of Metadata differences in Photo Managers and Online services

[PhilvS]

Is there a good overview of the differences (and pros/cons) of the way metadata is used (abused?) by iPhoto, Aperture, Photoshop, Facebook, Flickr, Shutterfly, Picasa, etc....?  I'm interested in a clear, concise format - book or on-line doc/website....

Related Topic: There is a conference held each year - Personal Digital Archiving.  Someone who has written the above document (Phil?) should present!  Anyone else interested should attend - I did last year, and will again this year. Here's link: http://mith.umd.edu/community/dh-events/event/pda-2013/

Thanks
Cheers!
Phil vS

[Phil Harvey]

Hi Phil,

I don't know of any overview describing how applications such as these treat metadata.  I try not to get into these details myself since I have my hands full with my own application.

- Phil

[PhilvS]

Phil,
Thanks for prompt replies. If anyone else hears of good overview material, please let me know.  There's got to be SOMEONE interested in this!
Cheers!
Phil vS