“Bump Article”

The plugin may help, but what I’ve done is one of two things. First, set the article in draft mode, make your changes, and then publish it. It should take on the new publish date and time.

Second, edit and make whatever changes you like, and then change the date and time in the Advanced Edit Post Options below the write post text area.

There’s a hack that will let you accomplish this through query_posts() (considering PostOrder requires an edit to the core, it’s no worse):

Around line 475 in classes.php (wp-includes/ directory), change:

$allowed_keys = array('author','date','category','title');

to:

$allowed_keys = array('author','date','category','title','modified');

Then in your theme’s index.php template, add this just before The Loop:

<?php query_posts('orderby=modified'); ?>

May require a bit more than that though, depending on your setup. But it will then sort posts by last modified (i.e. edited) date.