The fine of 899 million euros is for Microsoft’s failure to comply with a 2004 ruling and the “unreasonable” prices Microsoft charged developers for the information they needed to make software compatible with Microsoft products. Now the question: will Microsoft just pay up and go on with business as usual, or will it open up?

Today Microsoft announced a “new interoperability.” Microsoft promised, among other things, to open up cooperation with open source software, including distributing its APIs for its software and allowing open-source project to use them without fear of lawsuits. It already released its Office binary formats.

The European Union, however, is investigating Microsoft for antitrust violations and called bullshit on Microsoft’s announcement, noting that “today’s announcement follows at least four similar statements by Microsoft in the past on the importance of interoperability.”

If Microsoft is truly willing to cooperate with the open-source community, that is good news. But it would be shocking news, indeed. On the desktop, Microsoft is king. When it comes to the backbone of the internet, Microsoft is a very, very distant second to Linux. Microsoft almost certainly has something else in mind.