With the help of other users some bigger changes are coming for the site map module. Big enough to warrant a 6--2 branch I believe.
- Full support for i18n
- Adding theme_site_map_menu_tree() and theme_site_map_menu_item()
- Move message display from hook_help to theme_site_map_display()
- Change from select to checkboxes for books/menus/vocabularies
- Use the Checkall module on the settings page if it's installed
- Add a site_map.tpl.php for even easier themeing