That was an issue I had with the post: how can "non-relational" be a good thing about CouchDB? If you have relational data, then there's an entire theory (relational algebra) behind ways to interact with it that have clearly defined semantics. I can see that one may decide they don't need that, but I don't see how it's absence can be a good thing. Being non-relational frees CouchDB to provide different kinds of capabilities, but it's those capabilities that are a good thing, not the lack of being relational itself.

Rather, I think the author has confused "relational" with a lot of other properties of relational databased management systems - such as transactions and data integrity guarantees.