functions.php

<?php

/**
 * Display Posts Shortcode, Featured Posts 
 * Only display featured posts using [display_posts is_featured="1"]. Assumes
 * you've already set up a checkbox in metabox with key of 'be_featured'.
 * 
 * @author Bill Erickson
 * @link http://www.billerickson.net/code/featured-posts-display-posts-shortcode/
 *
 * @param array $args
 * @param array $atts
 * @return array $args
 */
function be_display_posts_featured( $args, $atts ) {
	if( isset( $atts['is_featured'] ) )
		$args['meta_query'] = array(
			array(
				'key'  => 'be_featured',
				'vaue' => 1
			)
		);
		
	return $args;
}
add_filter( 'display_posts_shortcode_args', 'be_display_posts_featured', 10, 2 );