I spoke to a cast member outside the Universe of Energy last week, and she said that she heard they were using all three previous voices, just digitally repairing them. She also said the ride would be divided into 3 sections, with each voice having a section of the ride. You know how rumors go...
I may have believed her, but that would be...kind of difficult to do considering the ride is supposed to be getting a new ending.
i've also had cast members tell me that if you wear 3d glasses in the haunted mansion then you see special hidden mickeys. they also told me that when the carousel of progress breaks down, they have a special area where it can be hand cranked to keep it turning. hence, i believe very few cast member rumors, except for a few particular cast members that i am good friends with.
They must have read "The Kingdom Keepers" too many times. ;D I'll put over with the "Epcot planned to open with a themed coaster in Japan, but Kodak squashed it due to the name" rumor.