I'm not sure what they are suggesting here. I see five applications with a similar looking startup screen and a music and video player with very basic controls. What is Documents supposed to do ? Let you edit any kind of document (good luck with that) ? Is this a viewer ?

Having essential applications follow a set of UI guidelines is nice, but it's hardly revolutionary, and it sounds like the goal here is simplicity. Unfortunately, it's often the case that something too simple turns out in practice to be useless. In any case, it looks the target is people with a lot of screen real estate to waste.