Hello,
I do this post for give you some ideas of things to add. For the moment I cannot help you because I have lot of work, but when I can I will try to help you.
My ideas are :
*add tags to photos
*flv videos supported (using iTheora fr example)
*customisables plugins via the admin interface
*customisables themes via the admin interface
*Exif data
*Adjust size of pictures in function of the web browser size
*Possibility of order album by date automaticaly
*right on albums
*multi users
*Full screen diaporama
if you have more ideas.
shenshei