Look, I live in Louisiana and anywhere in the south, hurricanes are a part of life. To make you feel a bit better however, there is a running joke around there that Walt sits up in heaven and blows hurricanes away from WDW. I am guessing he does the same for the cruise line. I have heard people say over and over again that the safest place to be during hurricane season is WDW!!!!
Enjoy your trip and remember they will not put you or your family in harms way.
Just make sure you buy the trip insurance.