hey man, i had a similar problem and wrote adobe. here’s their reply:
Thank you for contacting Adobe® Web Support for assistance with Adobe
Bridge CS3®
I understand that you are able to apply captions and other metadata in
Bridge, but when you view the files in other programs this information
appears empty.
We have released updates to Adobe Bridge CS3, and these affect the way
that metadata is stored and interpreted. You can choose the
‘Help->Updates’ menu option in Photoshop or visit the following
page to download and install the update manually:
http://www.adobe.com/support/downloads/detail.jsp?ftpID=3620