query-posts by popular?

Hi,

I need to do some fairly advanced styling on some posts and I’d like to query the data stored by WPP to output it, I’m not much of a database expert though so I’m not sure what my array should contain.

<?php 

			$featuredPosts = new WP_Query( array(

			    'meta_key'=>'????????????????????????',
			    'orderby' => 'meta_value_num',
			    'order' => DESC
				) );
			 ?>

				<?php if ( $featuredPosts->have_posts() ) : ?>

				<?php while ( $featuredPosts->have_posts() ) : $featuredPosts->the_post(); ?>

				<article <?php post_class('item-post block'); ?> id="post-<?php the_ID(); ?>">
				<?php the_title; ?>
			</article> <!-- end div post -->

				<?php endwhile; wp_reset_query(); ?>

				<?php endif; ?>

http://wordpress.org/plugins/wordpress-popular-posts/