We just returned from a weekend camping at Disney's Fort Wilderness campground with our children (ages 6 & 9). It was exactly what I would expect from camping at Disney World. The customer service is exceptional. The facilities are clean and well maintained and there is no shortage of activities for families. We were tent camping, so we were given a spot that had plenty of room for two family-size tents, one minivan, one pickup truck, and two golf carts. The kids had a blast riding around on the golf carts, swimming in the pools, and playing on the playgrounds.
All that being said, I would not recommend Ft. Wilderness to anyone looking to experience nature of have a quiet weekend hiking or bird watching. The buses ran all night and they camp sites are close enough to hear everyone around you. For me, it's about expectation. If you want the Disney experience in a tent, camper, or cabin, then this is a great choice. If you want quiet, nature, hiking, bird watching, etc., I would recommend looking elsewhere.
Overall, we had a great experience and my kids had a blast.