For my family, Disney World is one of those; Been there, Done that deals. I have family members that work for Disney, and we're able to go free of charge and I think that helped to wear off the novelty of the place. I think it's primarily for kids, my 11 year old daughter prefers to go to Busch Gardens, and my 8 year son has more fun at Universal Studios.
If you do go, find one of the resort areas to stay at. There all nice, with the exception of the sports resort. It's cheesy. I that that adds to the allure of "The Magic Kingdom" JMO:o