This is the Disney way now, and it has been since the early 90s when they installed Disney Afternoon Avenue. Even part of Tomorrowland was transformed to be Toy Story Funhouse in 1995.
When John Lasseter and Pixar were brought back into the Disney house, one quote I remember is that Lasseter didn't see why they couldn't have an attraction hit when the movie did. He was tired of seeing the attractions come out years after the movie is gone. Synergy at its finest.
A lot of that quote from JL frightens the Crap Legacy out of me. But in a theme park like DCA where even an overlay like Glowfest is considered a welcome addition by many, I think a temporary thing is perfectly fine. Tron Legacy truly belongs in Tomorrowland but DCA is the park that needs help and I think taking advantage of all those empty buildings in Hollywood Pictures Backlot is a smart move.
I'll accept this as a test to gage audiences and improve the things that will be permanent. There's a lot of potential for TRON to live in the theme park and I think something like this would help weed out the bad... all while promoting and creating more excitement for a movie that already has me needing new pants everyday.