I can't speak for the specifics of how they pulled it off- but since pretty much everything in the car is on the CAN bus, and the computers run Linux, so a special build of software that was timed to the music like those house light displays wouldn't be too far fetched to pull off. Mostly how did they sneak it by management? or was it sanctioned? I read earlier that there had been a posting with some explanation that got pulled. I find it very clever and certainly a good test of the door controllers. I know I certainly enjoyed watching it.
The earlier video of it today showed the Tesla employees describing it, and thanking being able to be given a certain room - I couldn't quite make it out - in order to present the display. So I am satisfied that they created and showed it with the approval - or at least acquiescence - of their superiors.
If I were so uncharitable as to criticize it - I'm not! I think it's GREAT! - I would venture to ask as to why they did not also include a raising and lowering of the cars via their air suspensions. Wouldn't that have been neat to see the cars bowing?
Super cool!! Certainly sancioned (GREAT PR for all of us waiting). Amazing the software can control that. I guess they figured they better be prepared for anything, so they wired everything they could...
Wonder if they would ever allow us to download that particular program into our personal Xs. You know, like another Easter egg. Seems just programming involved without added hardware no? Although I do wonder how they got the falcon doors to open so high?!?!