Format Comparison Between ODF and MS XML
http://www.groklaw.net/article.php?story=20051125144611543

Hudson, Alex, J. David Eisenberg, Bruce D'Arcus and Daniel Carrera
Groklaw
2005

Abstract:

There has been a lot of attention to the legal encumbrances in Microsoft's new MS XML format. In this article we'll look at the technical side, and try to show you how the design of these formats affect interoperability. After all, that is the purpose of open standards.