Most commented WordPress posts in the last week. See: http://JoshPress.net/blog/using-new-date-queries-wordpress-3-7

most-comment-last-week.php

<?php
$args = array(
	'date_query'          => array(
		//set date ranges with strings!
		'after' => '1 week ago',
		'before' => 'today',
		//allow exact matches to be returned
		'inclusive'         => true,
	),
	'orderby' 		=> 'comment_count',
	'order'	 		=> 'DESC',
	'posts_per_page'        => '5',
	'paged'			=> '1',
);
$query = new WP_Query($args);
?>