The subject of whether XML will replace EDI was a hot topic a decade or so ago. Although its use has skyrocketed over the years, XML has never supplanted EDI and most likely never will. The question was actually was actually a silly one to begin with, and seems even sillier now that we have the perspective of having used both of them over a number of years. It’s primarily an academic question anyway, since having the opportunity to make a choice between them is relatively rare.