File Info not saved (.gif) (Ps CS6 Extended, Mac)

Question

I'm not certain that I've been building my workflow properly before, so if this was not supposed to be supported, I'm open to that possibility:
Modifying the "file info" for a gif file (in my case, "General" tab, "Document Title" and "Description") doesn't actually get saved with the file - or, at least, if it is saved, it's not visible when re-opening the file.
I believe that I understood that metadata for .png format isn't supported, but I thought that .gif was. 
(Test case is easy: open .gif file, add a Title and Description, save, and re-open - information is gone).
Thanks for any help anyone has...

Answer 1

hi Chris & thank you for your response
it doesn't seem possible to add File > Info to a .png image in Photoshop itself. i've tried it a few different ways.
(shoot, actually i should try adding it again in Ps to a .png file and then see if Bridge can read it. hmmmm??)
in an other thread: [ http://forums.adobe.com/message/5642141#5642141 ] Gene told me that i could select Copyright and Contact Info from the Metadata drop down menu in the Save for Web panel to add the info to a .png image but this didn't work.
i don't know if Ps is having one of its "fits" or what but nothing seems to be working.
after a bit Gene was able to tell me that i can add File Info to .png files in the Bridge Cs6 or CC (no idea what the difference is between Ps Cs6 and Ps CC) and so i tried that and it worked.
however, it appears that Ps still cannot read the data/info when the .png image is opened in Ps itself. Only readable in Bridge.
which brings me to an other Q ... what's the point of Copyright info that can't be read? i am not being sarcastic i just really don't understand. granted, i need to read up on this topic but was hoping you could share your thoughts/knowledge w/me   oh, and if you have any handy links i would also much appreciate it. thanx 4 ur help!!