I have to disagree with you here. Graph DBs are a much more elegant way to store graph data, i.e. social media data, some forms of scientific data. But for the vast majority of relational database usage, i.e. finance, accounting, retail, medical records, human resources, academia, reservation databases, etc. the truly vast amount of databases we interact with indirectly all day long, these systems are firmly in the relational camp and that is not changing anytime soon. SQLAlchemy would very much like Python to be prevalent throughout all these industries, and is not just about social media applications.