In March, I brought a combination of cash and my check card. Where my check card is a VISA, I could use that anywhere they accepted credit cards and used the small amount of cash I carried around each day for vendors. It worked out really well for me. I just made sure that I had my cancellation numbers with me, in case I lost it (or it was stolen).
I've also heard that American Express has a travel card that you put money on (like traveler's checks) before your trip and use like a credit card. This sounds a lot easier than the actual traveler's checks, because, in my opinion, they're a pain in the butt to use.
Also! Don't buy disney dollars unless you're giving a few to a child or something. They're pointless, because they're like buying yourself a gift certificate. If you don't use all of them, you go home with a whole bunch of useless paper with mickey on it. (that cost you a lot of money)