They say that they need a week or 2 to get the card. BUT you can get the reward card at any Guest Services counter at one of the parks. They will look you up and give you the most up to date amount of DRD available at that time.
Then you just have to call the # on the back of the card to activate it.
Just make sure you bring your DISNEY VISA to the Guest Service counter.
I was able to do this very quickly last year at Animal Kingdom.