By summer 2010, we began work on adding social features […] to Gimme Bar, and CouchDB started giving us trouble. This wasn’t CouchDB’s fault, really. It was more of an architectural problem. We were trying to solve a relational problem with a database that by-design knew nothing about how to handle relationships.
Then he ended up using MongoDB, which as CouchDB knows nothing about handling relationships.
After using both, extensively (for a very specific application, admittedly), I firmly believe that MongoDB is a superior NoSQL datastore solution for PHP based, non-distributed (think Dropbox), non-mobile, web applications.
How can you assess the general superiority of a storage solution based on a “very specific application”? What does PHP have to do with that? Are MongoDB drivers superior to just using HTTP with JSON?
Finally the sane conclusion:
Bottom line, this story sounds like building a prototype while also deciding what tools to use. Nothing wrong with that. But the title(s) should be different.