[Jetpack] Change og:title value to be all uppercase

plugin.php

<?php
/*
 * Plugin Name: Uppercase og:title for Jetpack 
 * Plugin URI: http://wordpress.org/extend/plugins/jetpack/
 * Description: Removes Jetpack's default og:title tag, and replaces it with an uppercase og:title 
 * Author: Jeremy Herve
 * Version: 1.0
 * Author URI: http://jeremyherve.com
 * License: GPL2+
 */
function jeherve_capital_title_og( $tags ) {
        global $post;

        if ( is_singular() && $post ) {
                unset( $tags['og:title'] );

                $tags['og:title'] = strtoupper( get_the_title( $post->ID ) );
        }
        return $tags;
}
add_filter( 'jetpack_open_graph_tags', 'jeherve_capital_title_og' );