"Guess what? I'm not a robot." It expresses the simple and the profane. It takes an accusation of inhumanity and turns it into a rhetorical question connected to a statement of tautological fact. Since we traffic in irony, it helps that an undulating synth-progression provides the background for an affirmation of a human heartbeat. Other than Marina's singular vocals (think Regina Spektor meets Imogen Heap), there aren't any human hand-prints on this song. It is almost intentionally not human.
After The Killers debated our humanity last year, you'd think this act would be tired. Well, guess what? It's not. Discussion of existence and red-blood-heart-beating definition won't get old. You can't program that debate into your personal device and wait for the right application to tell you what to feel or what to say or who to turn to. (Pedantic? Sure.) Zeros and ones can beat us in chess and take us to the moon. They fly our planes and they fight our wars. The binary system is, in fact, completely responsible for what you're reading right now. About 75% of the time, we live in the Matrix. Not today. Guess what?
Listen :: Marina and the Diamonds - "I'm Not A Robot" [Starsmith's 24-Carat Remix]
Bonus :: Marina and the Diamonds - "Obsessions"