It does validation on the front end to ensure the credit card number is an actual, valid credit card number and nothing else. It does not verify the owner of the card, nor if funds are available. Just "xxxx-xxxx-xxxx-xxxx' is a valid "xxxxxxxxx" (Visa, MC, Amex, whatever - pretty comprehensive list) number. We can deposit that snippet right into our code toolbox. It could be ajaxed up too.

Nice find!