I concur with Nick_A's suggestions... both very good. Also surprisingly good is Lee Cockerell's Creating Magic. It's essentially leadership advice... but a lot of tidbits about the "zen" of Disney as well.
Presuming they're referring to Disney Files magazine, I'm not seeing anything about subs, but there is an interesting note that since Ariel's hair is supposed to behave like it's underwater, her hair will be animatronic, too. As in, her hair will be animated.
As others have said, this is very smart discounting... does anyone remember "surprise fastpasses"? Back in the stone age days (you know, before Soarin' :lookaroun), if you ran right over to Mission: Space or Test Track and got a fastpass right at rope drop, you also got a "Surprise Fastpass" to...
One thing we're quite perhaps overlooking is the future potential once the technique is perfected. We're fixating on "that big ugly projector," but the usual case with patents/invention is that when you're doing early research, the first step is to make it work, no matter how unwieldy it is...
Obviously they'll use this to achieve the interactive video/photo aspect promised for the nightly castle show when they turn it into a giant cake for the 40th annivesary next year.