I was a bit reluctant at first, maybe I still am. In a way it sounds like 2 or 3 songs in one, plus the kindergarten piano and the overall aggressiveness. Anyhow, it made me laugh (in a good way).
Be sure to watch Björk in the Volta video podcast including an interview and behind the scenes footage.
One more Björk thing: I adore her live cover of No Limit by 2 Unlimited.
She should record a studio version of the track.