An interesting bit from the AARP Bulletin, January 2006, page 6:
“Heritage tourism” is hot these days, thanks to travelers who are more interested in visiting historic sites than in negotiating ski trails or white-water rapids. As boomers age, an official of the Colorado Historical Foundation told the Denver Post, “they’re going to be more likely to visit a historic site than climb a fourteener.” (That’s a 14,000-foot peak.)
If it's true, this seems like good news for Colorado's NG railroads, and others too.