I know how to change the notification email with a hook.
add_filter("gform_notification_email", "change_notification_email", 10, 2);
function change_notification_email($email, $form){
return "mattsex@gmail.com";
}But how do you change the BCC with a hook?
You can use the gform_pre_submission_filter http://www.gravityhelp.com/documentation/page/Gform_pre_submission_filter to change the $form['notification']['bcc'].
[php]
// change 53 here to your form ID
add_filter('gform_pre_submission_filter_53', 'add_bcc');
function add_bcc($form){
// add your email addresses here
$form['notification']['bcc'] = 'administrator@example.com';
// return the modified form object
return $form;
}