I'd have to disagree with most of the postings here. I think, done tastefully, a show about Walt's life using state-of-the-art audio-animatronics would be quite amazing. Notice I said "tastefully." I think Great Moments with Mr. Lincoln at Disneyland is one of the best shows ever created by Disney, but the recent update (fortunately not playing during the 50th) is an abysmal Sounds Dangerous! with Honest Abe. This is what can happen if you don't truly respect the subject you're supposed to be honoring.
Similarly, a show about Walt's life could be wonderful, if for no other reason than to make sure no one ever forgets that it was all started by Walt...not just a mouse (or a corporation). Kids need to know he was a real person, and while the One Man's Dream attraction is a great tribute, I think an audio-animatronic show would be even better. Of course, they would have to use his actual voice. I'm thinking maybe it could open with Walt sitting on his desk, similar to the way he introduced many Wonderful World of Disney/Color/etc. episodes. He'd then narrate the story of his life, with curtains and/or scrims opening to reveal scenes from his childhood, his early years, the Studios years, and the theme park years.
Maybe non-Disneyphiles wouldn't find this as interesting as I do, but enough people seem to like One Man's Dream that I believe it would have an audience. I know Walt didn't want an audio-animatronic of himself made, but then he didn't want cotton candy or ferris wheels in his parks, either. At least this could be a good way to go against Walt's wishes. He might even approve...not that I want to start that kind of thread again.