Yeah I would say those are key value document based DB. Just silicon valley hipster coming up with cool names to call something different so it is a bit easier for developer to use. Anything does permeant storage are DB.
I certainly don't agree that 'anything that does permanent storage is a DB'. Not many people would call their hard drive a 'database'
I personally think that they all have a place and are very useful tools for certain situations, depending on the problem.