Hi Jamie
I was going to PM you my update_product.php to see if you could see why it is not posting price and description. But you have your PMs on not allowed.
I added the code below to my update_product.php as it has been modified. Is there anything else I need to add?

Code:
 
 //AutoFacebook
    $store_name = "My Store"; // store name i.e. "Mary's Car Shop", or "MikesCupcakes.com."
    $store_url = 'http://www.mystore.co.uk'; //path to your store without the trailing "/"
    $cur = '£'; //change to your currency symbol. Assumes symbol come in front of numbers
    $new_message = "New Product!";  // change to whatever or leave the same. i.e "New Cupcake!"
    //your facebook developer app info.
    $appapikey = 'mykey';
    $appsecret = 'mysecret';
    $user_id = 'myid';   //id of your facebook store page
    $infinite_session_key = 'Mysessionkey'; //from facebook app
// No Need to edit below here.
    $prod_image = $store_url . "/images/" . $_POST['products_image'];
    $price = $products_price;
    $prod_url = $store_url . '/index.php?main_page=product_info&cPath=' . $current_category_id . '&products_id=' . $products_id;
    $prod_name = implode(" ", $_POST['products_name']);
    $prod_description = implode(" ", $_POST['products_description']);
include_once 'facebook/php/facebook.php';
$facebook = new Facebook($appapikey, $appsecret);
    $facebook->api_client->user = $user_id;
    $facebook->api_client->session_key = $infinite_session_key;
    $facebook->api_client->expires = 0;
$attachment = array(
      'name' => $prod_name,
      'href' => $prod_url,
      'caption' => 'Price: '. $cur . $price,
      'description' => $prod_description,
      'media' => array(array('type' => 'image',
                             'src' => $prod_image,
                             'href' => $prod_url)));
$action_links = array(
                      array('text' => $store_name,
                            'href' => $store_url));
$attachment = json_encode($attachment);
$action_links = json_encode($action_links);
$facebook->api_client->stream_publish($new_message, $attachment, $action_links);
//end of autoFacebook