Canonical was (enthusastically) using early versions of SQLAlchemy. But the pace of SA's development in terms of their immediate business needs did not suit them and they lost confidence in the codebase, so they abandoned and rolled their own ORM which became Storm. They later decided Storm would be their "flagship" open source offering from launchpad. Since then SQLAlchemy has had nearly twenty releases and virtually all issues Canonical had with SA have long been resolved. Storm as a project has an intentionally narrower scope than SA, lacking such features as schema generation support, table reflection, and even a connection pool (which they may decide to add in a later release), although its object-relational API is nearly indistinguishable from that of SQLAlchemy. »