I doubt there will be anything like the Epcot Future Technology Conferences of the 1970's to guide this effort. You are right that people's expectations of the future have changed, ranging from the extremely shallow (like what the next new cell phone is going to be), to some pretty harsh cynical views based on current world events. Coming up with any message is going to be suspect in someone's mind.
I know that the 1982 message from the corporate sponsors, "this is what your future will be, trust us", is not even plausible in today's public. A wonderful new future brought to you by Exxon -- really??! That was barely palpable even when Disney was supposedly pushing the message. So perhaps the message now needs to be, "here is what your future can be, you can help make the difference" or something similar that places the ability into the hands of the guests? I don't know -- I'm just writing off the cuff here.. Right now they are pushing after-park-hours tequila sampling as an educational experience. (I know that was a part of my educational experience in college.) Unfortunately, that's currently where the thinking is with the folks at Epcot -- well-intentioned, but off the mark.