There's an assumption that "dumping it into Hadoop" is the equivalent of "throwing junk mail on the pile for later" or "copying the contents of my desktop to the corporate file share." Its not, or doesn't have to be. You can certainly do that with a hadoop cluster, but to make actual use of it you still need to structure the data. Even if its only enough for the MR algorithm to get some traction, you still need some structure to get some traction. Usually that structure is some variation of a dimensional warehouse model, often in "super transaction" form.
Now, people think there's some magical way to turn a data lake into profit by waving the Hadoop wand at it. Especially Marketing people. This is much the same kind of thinking you see in application developers who think that if they're just allowed to use flexible-schema systems like Mongo or Couch they can do JIT semantics. But in both cases, to make sense of the data over time you need a consistent schema to store the data in. We all know that, as database developers. And a JIT semantics is fine if you're dealing with stuff you don't need to track over time.
But Netflix is concerned with behavior over time, so they can't use a JIT semantics.
This principle is independent of anything Codd might have formulated, and that's in part because to make relational work right you need some kind of consistent and stable semantics. Codd assumes you've got it together. So the principle doesn't require relational-like-SQL-Server relational, but it still needs to be a semantics. Codd's normal-form semantics happens to be a particularly reliable to way to manage semantics in general, but any stable ontology will work without being in third normal form. (It'll be a pain to manage, but oh well.) Similarly, if you want me to report on the contents of your document model, you better make sure I've got something to report on that doesn't require daily updates to CASE statements or I'm going to get it wrong.
So Netflix is using Hadoop in a virtuous way, and one that doesn't actually violate any of our relational db instincts. Its just that the application developers who are all hot on Netflix's Hadoop cluster don't understand the implications.