If you think about it, every single attraction at Walt Disney World that is considered a thrill-type attraction, is based off an original idea incorporating an existing theme or story treatment.
Space Mountain
Splash Mountain (obviously based off of the Song of the South, Uncle Remus: His Songs and Sayings)
Big Thunder Mountain Railroad
the late and much missed, Alien Encounter
Mission Space
Test Track
Soarin'
The Twilight Zone Tower of Terror
Rock 'N' Roller Coaster
Expedition Everest
Countdown to Extinction
Kali River Rapids
See the trend? I'm not saying that Disney would never base a thrill-type attraction on one of their or Pixar's beloved films. But seeing as this entire discussion is based on one or more persons' thoughts of a rumor, I really would like to see it dismissed. It's just ridiculous, a pipe dream of sorts. While I agree with you folks irritated at me, that I shouldn't ever guarantee the probability of it not happening, I disagree that you should be so hard-pressed to see this thing happen.
As fellow dreamers, hopefully doers and most certainly, in my opinion Respected thinkers, I would hope that our boards be used for purposes more proactive in truly seeing Walt's vision. This is still Walt's dream and Walt's company, dead or alive. There are so many moderators and members on these boards that are somewhat and somehow connected to the company, why not rant on truly original ideas that will truly bring the company back to what it was founded for.
"Adults are interested if you don't play down to the little 2 or 3 year olds or talk down. I don't believe in talking down to children. I don't believe in talking down to any certain segment. I like to kind of just talk in a general way to the audience. Children are always reaching." - Walt Disney
This is, to me, what the original EPCOT really stood for. It was a place where children and parents could "laugh, play and learn together". It has become a place to prostitute Disney's most successful films and make loads on merchandise (not on a whole, but we see a largely growing trend throughout the resorts and parks).
"We have created characters and animated them in the dimension of depth, revealing through them to our perturbed world that the things we have in common far outnumber and outweigh those that divide us." - Walt Disney
Let's think a little deeper and a little more globally. Disney has influence, power and definite responsibility to teach through their amazing creative flair and the spectacular technological advances that are at their hands.
Just because attractions with thrill are highly in demand, attested somewhat to humanities waning attention abilities, does not mean that they cannot or should not be somewhat educational or effective in moving a person(s). Let's think Test Track, Mission Space and the environmentally aware Kali River Rapids/Expedition Everest attractions.
~Chris