Mercifull on "[Plugin: Jetpack by WordPress.com] Custom og:image for homepage not working"

<?php
/*
Plugin Name: Matts OG:image fallback
Plugin URI: http://www.frome.fm
Description: Functionality plugin to add default open graph image to homepage when no featured image found. Also adds @FromeFM to a Twitter meta tag. Requires Jetpack. Code from http://jetpack.me/tag/open-graph/
Version: 0.4
Author: Matt Sims, Automattic
Author URI: http://www.mattsims.com http://www.jetpack.me
*/

function fb_home_image( $tags ) {
    if ( is_home() ) {
        // Remove the default blank image added by Jetpack
        unset( $tags['og:image'] );

        $fb_home_img = 'http://frome.fm/wp-content/uploads/2013/02/Vote-FFM-slider.jpg';
        $tags['og:image'] = esc_url( $fb_home_img );
    }
    return $tags;
add_filter( 'jetpack_open_graph_tags', 'fb_home_image' );
}

function tweakjp_custom_twitter_site( $og_tags ) {
	$og_tags['twitter:site'] = '@FromeFM';
	return $og_tags;
}
add_filter( 'jetpack_open_graph_tags', 'tweakjp_custom_twitter_site', 11 );
?>

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