Enhancements:
Undo on most every operations
"Vector field" alignment.
Apple Script support down to image processing basics
Customizable process class to call scripts.

If a picture is already in the list, display an alert box and don't add it.
If a movie is already in the list, ask the user if he wants it to replace it.
Add a "dirty" flag on the movies to detect the add of a "non edited" movie.

Export all the selected pictures to a QuickTime movie.

Preview the process in a small square before processing the whole image.

Maybe:
XML file read/write.
Bundle type document to store images and XML together.

To be put in user preferences: