Who sings the "Let's Hum" song in the new Prius commercials?

Oh man, it’s been stuck in my head for hours now!

Link, please!

It seems that they don’t want to reveal who the “artist” was… I found credit lists like this on a few websites, and none mentions the singer. Since the story is supposed to be from the point of view of a child, some peopls are guessing that a child is singing, though it doesn’t sound like a child to me. It sounds like one of the several artists who are sing in the style of Feist, Pomplamoose, The Bird and the Bee, etc.

Sorry, @filmfann. Here it is.

It sounds like Feist