There is no hype for NoSQL or MongoDB on HN. In fact it is the complete opposite with every one trying to push SQL and PostgreSQL for every use case under the sun.
threeseed is famously (to me) HN's personal MongoDB cheerleader. It always fascinated me. When I read the upstream comment my first thought was "I wonder if threeseed will show up."
Why couldn't they be serious? NoSQL got big somehow. There was obviously a big push and support for it when it became big. How would HN be immune to this when it can't even spot an obviously fake story about Apple acting like cartoon villains?
I wasn't giving an example of a current hype -- just of a hype.