Koos van Strien contrasts data virtualization with data warehouse automation:
From a certain viewpoint, one could state that Data Virtualization is focused on the way the world should work: when integrating data, one shouldn’t have to store it everywhere. Why not let the system decide when to store? For some, to adopt this view might mean a paradigm shift: suddenly, the Data Warehouse the go-to integration point any more!
From this viewpoint, DWA a tool “from the trenches”: after years of struggle and hard work to build our warehouses, we’ve developed some smart ways to automate our warehouse-building based on abstract models.
Worth reading the whole thing.