I think all of you guys are getting a little too serious about this
Here's my take: even in a 100% Microsoft shop, .pptx is a pain as much
as .xlsx and .docx. And yes, I know about the free
"fileformatconverters.exe", thank you very much. It does not work on my
Microsoft cell phone that does not read .pptx, but does read .ppt.
.pptx is a pain in the arse. I don't care if it's standard, legally
standard, IETF approved, de-facto standard, or anything. Even if one is
using a newer version of PowerPoint, one can "save as" .ppt.
.pptx is just like HTML in a mailing list: just say no.
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