I personally don't believe in a doom-and-gloom future. Despite the cynics, I think that life will be better... much better. I would not want to have had grand-parents' lives or, gasp, my great-grand-parents' lives. The good ole days are good only because we get caught up in how hard we think we have it now. Our lives are much better now... life expectancy is longer than ever... many diseases have been cured... education is better (despite the slow invasion of socialism in our country)... transportation is better... heck, our food is better (yes it is!).
Imagine what life will be 100 years from now! Cancer will be cured, transportation will be even better (instant teleport to China?), what we now consider the mysteries of science will be taught in grade school, food will be produced in such a way that famine exists only in history books, the dependence of oil will be as outdated then as the need for steam engines is now, our life expectancy will well exceed 150 years... And why not? Can you imagine having lunch with your ancestors from 100 years ago and trying to explain space travel, the Internet, HDTV, DNA tests, or DisneyWorld? I bet they would laugh at you.
And what does this have to with Disney? Well, the only way WDW can exist in 100 years is if the company continues to innovate - to stay just ahead of the imagination of those who wonder what the world will be like in 100 years. However, if the Disney Company disappears (quietly or abruptly) one day, I have no doubt another genius will appear from nowhere and spark the imaginations of our grandchildren or our great-grandchildren.
I think the future's just fine.