At what  point does a developer stop being simply a developer and turns into a software architect. Or in other words, what's the minimum job description of a software architect?  
What defines a software architect?
architect
I think there is no best answer than:An architect do architecture.So if you do architecture, you are an architect. Maybe you asked for what is a good architect ? Or maybe a predefined task list?In addition to the other excellent answers, including the one from Jim Leonardo, please read this document:Who needs an architect - Martin FowlerMy opinion ?Architecture is a team sport