I called BankOne becuase I am in the same predicament. They didn't volunteer any info, but upon pressing them, I got the following info:
If you have rewards on your Disney Visa, but not enough time to get the card before you leave, you can pick one up at Guest Relations at Downtown Disney or Dis Westside. You will need your Dis Visa card and drivers license, but they will be able to check your account and issue you a rewards card right there with your rewards on it.
One thing to keep in mind, which came into play in my situation...the rewards pts aren't actually available until the billing cycle following the one in which you charge. In other words, they aren't immediately available. If I charge something now, the pts accrued won't show up until AFTER my billing cycle Dec. 10th.
Sally