[Jetpack] Deactivate Twitter Cards and / or Open Graph Meta tags.

plugin.php

<?php
/*
 * Plugin Name: Disable Jetpack Open Graph tags and Twitter Cards
 * Plugin URI: http://wordpress.org/extend/plugins/jetpack/
 * Description: Disables Jetpack Open Graph tags
 * Author: Jeremy Herve
 * Version: 1.0
 * Author URI: http://jeremyherve.com
 * License: GPL2+
 */
// Disable both Twitter Cards and OG tags
add_filter( 'jetpack_enable_open_graph', '__return_false', 99 );

// Disable only the Twitter Cards
add_filter( 'jetpack_disable_twitter_cards', '__return_true', 99 );