gistfile1.php

<?php

// Don't email webmaster for comment moderation
function pref_dont_email_webmaster( $emails, $comment_id ) {
    $webmaster_email = get_option('admin_email');
    if ( $emails[0] == $webmaster_email )
        unset($emails[0]);
    return (array) $emails;
}

add_filter( 'comment_moderation_recipients', 'pref_dont_email_webmaster', 10, 2 );