I have multiple users adding content to restricted categories (using RoleScoper) in my Wordpress setup that don't show up on the homepage (custom template with query_posts()).

I'm looking for a way to "promote" the submitted content to the homepage by adding it to another category.

My loop code looks like this:

<?php
query_posts($query_string . '&cat=-37');
if (have_posts()):
    while (have_posts()): the_post(); ?>

This will exclude all posts in category 37. However, even if I add the post to a different category it still gets excluded.

Is there a way to exclude a post if it belongs to just that one category?