After playing around in nosql land for the last 3 years I've landed at postgresql as my go-to sql alternative although the market will keep being fragmented.
edit: json support in combination with a less fanatic approach to normalization can approximate some of the benefits a nosql model can while maintaining the bulk of the tried-and-tested flows in a relational database.
I think he probably means that certain Postgres features like hstore and JSON support allow it to be used in situations where he once would have chosen a no-SQL solution. This has been my own experience.
edit: json support in combination with a less fanatic approach to normalization can approximate some of the benefits a nosql model can while maintaining the bulk of the tried-and-tested flows in a relational database.