OpenDocument vs Microsoft OpenXML - Part I

For a technical comparison see part II of this article.

What's the difference between OpenDocument and Microsoft's "OpenXML"?

OpenDocument Microsoft OXML
Is an ISO standard
ISO/IEC 26300:2006
Not an ISO standard
While OXML is an Ecma standard, Ecma standards are not considered international standards for the purposes of international law. That's why ISO approval is important. Gartner predicts that ISO will not approve OXML as an ISO standard.
Is vendor neutral Is a one-company format
The purpose of Ecma TC45 is to produce a format "that is fully compatible with [the format] submitted by Microsoft". In other words, they cannot make any substantive changes to the format. They can only rubber stamp it.
Many implementations
applications list
ZERO implementations
There isn't a single product in the market that implements the format. Not even from Microsoft.
5 years of development
(in a standards body)
1 year of development
(in a standards body)
Readily intuitive to those familiar with HTML or DocBook.
See the technical comparison for details. The cryptic nature of OXML markup leads to higher development costs.
Proven technology
Reuses proven standards like SVG and XLink.
Reinvents the wheel.
Easier to implement
700 pages
3MB spec
Reuses existing standards.
Harder to implement
4,000 pages
24.4MB spec
Reinvents the wheel.

And what does OXML give you in exchange for this?

We are yet to see an example of something that Microsoft OpenXML can do and OpenDocument can't.

See part II for a technical comparison