How to Rename a Template File?

If i have pages that point to somefilename.php and want to change the filename to betterfilename.php, can I leave the template comments unchanged without manually changing all the pages?

/*
Template Name: Some File Name
*/

Chris gave me some good insight, and I appreciate the filter func. But I wound up changing the db through phpMyAdmin:

UPDATE wp_postmeta SET meta_value="new-filename.php" WHERE meta_value="old-filename.php";