If the changes occur, I'd be interested to see how far they're willing to go to make the story more contemporary and cover recent times. There's a pretty strong tradition in Epcot's educational dark rides (and Disney's old science documentaries of the 50's and 60's) of starting everything with the dawn of man or the first cooling of the Earth's crust (see: Spaceship Earth, Universe of Energy, Living Seas, the old World of Motion). I've always thought that that's kind of a cumbersome way to tell stories.
As long as the new Spaceship Earth still bears the creativity of the Imagineers and doesn't become a big Siemens infomercial, I think it would be good to advance dark ride storytelling a little bit.
In general, dark rides are an area where WDW could really still assert it dominance if it wanted to. They don't really try to compete on thrill ride intensity; their deal is storytelling. It's a shame that good crazy dark rides aren't really a priority anymore (at least in the states-- Sinbad's Seven Voyages at TDS and Pooh's Hunny Hunt at TDL are wild).