Is there a name for very long scrolling web pages like the Android KitKat page? I am trying to Google for CSS tutorials and other examples, but have no idea what the design is called.
These guys call it a layered site or sandwich site:
websites containing clear and concise sections layered on top of each other.
I prefer this term over "Parallax scrolling" since parallax scrolling is more associated with multi-layer horizontal scrolling that creates the illusion of depth to the viewer. (Background moves slower than foreground, it's the same effect when looking out of a car window)
I've heard it referred to as single-page design or a single-page website. For the specific kind you are talking about, I would use the term scrolling single-page website.
Here's a link to some of the great example of Parallax Scrolling websites.