This was before XML acquired the, ahem, "seriousness" of the rep it now has.  Really, I don't think the exact format mattered, because it would only be used between the processes themselves, you'd use some kind of formatter on the output end to produce something actually readable.  The transport format isn't what killed it; one might argue that flat text is good enough, and that's what killed trying to create an alternative inter-pipe format.<p>I still think it's a good idea, but even the success of powershell (how often do you hear of someone actually using it?) says it's not going to go anywhere.