If you mean reference them inside the mail template as in {$card.type}, etc., then no that does not work. I even tried modifying the payment_cc.php file to say something like this:
$order_details1 = "$card_type"; (with and without the quotes) and that did not work either. For now, I've just taken out the words and had it output everything on one line, hoping the order processing people are smart enough to realize which part is the type, #, and exp. date when they see it.
But that's not a very elegant solution. I can't see it being terribly difficult to change (or add to) this logic but I am just missing where to do it.