Customize edit.php Pages listing in dashboard to show only pages with a particular template applied?

The question says it all, I think. I’d like to create a new submenu page using edit.php which will only display pages which use a certain template file (or files).

Possible?

Try this:

<?php

// add submenu page
add_action('admin_menu', 'add_template_submenu');   
function add_template_submenu()
{
    add_pages_page( 'My Template', 'My Template', 'edit_pages', 'edit.php?post_type=page&template=your-template-file.php');
}

// check for the template name passed in $_GET and add it to the query
add_filter('parse_query', 'filter_pages');  
function filter_pages($query)
{
    global $typenow, $pagenow;
    if ($pagenow == 'edit.php' && $typenow == 'page' && $_GET['template'])
    {
        $query->query_vars['meta_key'] = '_wp_page_template';
        $query->query_vars['meta_value'] = $_GET['template'];
    }
    return $query;
}