The light --- true interoperability, genuine openness, user control over their own data/documents and choices over their ICT --- is visible. And there are technologies that exist to help us reach it, such as OpenDocument Format.
But Microsoft remains allergic to light. It's "big" move is not about INTERoperability; it does not "build a technical bridge between the Open XML Formats and Open Document Format(ODF)," as advertised by MS.
Instead, it will build a vacuum cleaner (a "hoover" for you Europeans) by which MS uses the Open XML Translator to suck in any documents created in ODF. Or for you Star Trek fans, a giant tractor beam pulling ODF documents into Microsoft's proprietary orbit.
Sam Hiser describes it perfectly:
The tool [will] change ODF's open XML content into MSECMAXML's corrupted XML. That means Office 2007 -- a product not in circulation -- will one day be endowed with the ability to open an ODF file and save it as the Microsoft "Open XML" format . . . ODF files are being shifted into MSECMAXML, possibly the most proprietary format ever proposed in the history of standards. MSECMAXML is a private implementation of open XML so clogged with binary flotsam & jetsam, to which only Microsoft customers will ever gain access.Interoperability is a two-way street. Until MS enables direct, native support for ODF in its software, it is not offering interoperability in any way. Here's another good article on the initial misreading of the news.
Until then, all you hear eminating from Redmond is a giant sucking sound.