I had the opportunity to do the Halloween event at the Magic Kingdom during my recent trip. Last night to be exact. The ticket price was about $35 and it was a bargain from my point of view. Not only were there all sorts of special touches just for this event, but the crowds were non-existant. We were able to walk right on most rides.
Overall, in the 5 hours we spent at the park (7 pm to midnight), we were able to do everything that usually takes us a day or two, without the rushing, standing in line, and crowds normally associated with the park. Add to that the "trick-or-treating", Halloween parade, HalloWishes fireworks, the plethora of costumed castmembers, and extra touches and it can't be beat. One of my favorites was the special attention the Haunted Mansion got for the event.
Again, I have to give it to Disney on their attention to detail and their incredible ability to mobilize people and get an enormous amount of work done in a short period of time; and, keep it invisible from the visiting public.