A singular OS that acts on well defined abstractions and interfaces making the number of resources the massive machine uses transparent. Software won't be the only thing changing to support this shift in large scale computing but hardware as well. Would this type of machine be autonomous with little user management? AI could assist the machine in optimizing configuration. Pretty soon it could interface with drones that repair hardware and even add new nodes. Zero configuration environment. The operator simply tells it what it should be running, until Skynet is unleashed.