The card pictured on that page[1] looks nothing like the payment cards they introduced, it is just a movie clip. If they want to claim that their implementation is valid they should show the validation for a payment card.
That's because these guys submitted using a "Player card" which is meant for embedded video streams, then swapped out the content for their widget after getting approved. A total bait-and-switch.
Player cards are meant for online video players, not any sort of interactive virtual content. Twitter wants to keep experiences consistent across platforms -- for mobile, Player card users are supposed to provide direct links to media streams. The docs are fairly clear on this. This whole thing just stinks of media stunt.
http://rbn_prod.s3.amazonaws.com/blog_images/2013/04/Screen-...