Cool info, and thanks for the links! I agree about XML. I think one reason XML is annoying is that it lives in both worlds -- human-readable, but able to encod

Cool info, and thanks for the links! I agree about XML. I think one reason XML is annoying is that it lives in both worlds -- human-readable, but able to encode arbitrary machine structure. But with OmniGraffle, for example, it seems like XML is a suboptimal choice because you shouldn't need all that XML structure getting in the way -- if you know what data to put where in the document, why throw all these tags around it? So like you say, XML's main advantage seems to be that you can use an off-the-shelf parser; but it doesn't really seem worth it. However, I still think plain text can be a good choice, I just would be less afraid to define my own specification. But I feel like I would rather use an extreme -- binary data (which would require custom serialization) or plain text (which would require custom parsing) -- over something general-purpose and verbose. Disclaimer: I am not a professional software engineer and do not have experience with large systems. My opinion might change after I got my hands dirty.