This episode is kind of like an enigma wrapped in an enigma. Throughout two seasons the machine has, largely, served Harold. All the while it was becoming more cognizant of itself until Harold's "failsafe" measures circumvented his own administration. The machine has reached total self-realization enabling it to manipulate, seemingly, all threats by using all parties to it's own means. This is brilliant as it is now what the ultimate Ai is supposedly capable of: directing the destiny of itself as well as all it watches. Now, Harold has the big task of resuming the administrator job, but will the machine allow it even as it may still allow him back in the "loop"?
This finale wasn't conventional and is better for it. Being more about wrapping up so many story-lines served faithful viewers while presenting mysterious questions alike. Finally, it serves notice things have morphed as if a quantum shift is in the future for next fall (Carter's character being a prime example). So, no traditional "cliffhanger", but an imminent game changer is afoot. Brilliant as so many are lined up to attempt to control what is now, possibly, impossible to contain as it once was. The end effect is the best: we can hardly wait to see how this proceeds!