Will Future Updating break this plugin?

Great idea…
When I wrote the plugin my intentions were to keep it as light weight as possible, so creating a settings page / box in the admin to add the image was beyond what I was willing to do. That being said, unless there is a major update to the WP core, it is highly unlikely that this plugin will ever get updated.
If the functionality is important to you, you can edit the plugin file to add that functionality, and I would be willing to give you access to the SVN to updated it in the repo.