Just to state or perhaps even emphasise the obvious, OOXML is a very large stack of proprietary Microsoft technologies, which directly contradict and antagonise existing standards, and not by coincidence. Microsoft has always established itself separately from the rest of the industry, as the following quote immediately reminds us:
"We want to own these standards, so we should not participate in standards groups. Rather, we should call 'to me' to the industry and set a standard that works now and is for everyone's benefit. We are large enough that this can work."
We already have an open standard for mathematical formulae and notation, it is called MathML and is published by the W3C math working group.
OOXML ignores this and uses its own Microsoft-specific Maths language.
We already have an open standard for vector graphics called Scalable Vector Graphics. This was produced to replace vendor specific formats such as Adobe's PGML and Microsoft's VML.
OOXML ignores this and uses Microsoft-specific VML.
We have a specification (RFC 3987) for UTF-8 capable Internet addresses. This allows URLs to be written in any language.
OOXML ignores this and can only use Latin characters in URLs, so speakers of Chinese, Japanese, Korean and many other languages are plain out of luck.
Some of the Microsoft comments have just been leaked out of the ECMA fortress. Microsoft continues to ignore the Muslim world, and they don't want to correct its WORKDAY function in order to 'do not break backward compatibility': "Weekend days (Saturday and Sunday) are not considered as working days."
The world should be pleased to note, that with the approval of ISO/IEC 29500, Microsoft's Vector Markup Language (VML), after failing to be approved by the W3C in 1998 and after being neglected for the better part of a decade, is now also ISO-approved. Thus VML becomes the first and only standard that Microsoft Internet Explorer fully supports.
We wrote a lot more about this earlier today. It's bad news for the Internet as well. Now is the time to advocate ODF and ensure that OOXML gains no traction.