The 420-metre (1,378-foot) building's apartments would spin a full 360 degrees, at voice command, around a central column by means of 79 giant power-generating wind turbines located between each floor.
Sounds like one apartment per floor. And the apartments don't go up and down. Just around. At the apartment owner's choosing (and possibly randomly when not given commands).
The elevator would be in the central column around which everything rotates.
I would be worried about having a wind farm above and below me. I don't know how much noise those turbines make, but a row of giant metal fans whirling just outside my floor and ceiling would be a little disconcerting.
I'd also worry about the building's balance, if everyone decided to move to the same side at once. I'm sure he's taken that into account somehow, but it seems like it could be a problem.
As for each configuration being once in a lifetime... That's up to the residents, isn't it?
Must admit, though, that all of this reminds me of "Isaac Asimov's Robot City," a series of books by various authors based loosely off of some of Isaac Asimov's ideas. It takes place in a city built out of "chemfets," microscopic cell-like robots that connect to form a greater whole. The entire city is effectively one giant fluid robot, and it reconfigures itself as it deems necessary and efficient. So you can go to sleep on the 65th floor and wake up on the 89th or the 12th, depending on how the rest of the building has flowed around your apartment. A little disorienting for the residents at times...
