The Open XML slugfest at ISO is over, governments around the world select ODF for document interoperability. But the proprietary binary office productivity file formats are still widespread. Former Open XML evangelist Doug Mahugh announces a "Binary Format Plugfest" for October 18/19:
Microsoft subject matter experts from both the support organization and the product team will be onsite to answer questions about the Binary File Formats. This Plugfest will be a great opportunity for you to test your [Binary File Format]BFF implementations and receive immediate feedback and assistance from Microsoft.
http://blogs.msdn.com/b/dmahugh/archive/2010/08/18/binary-file-format-plugfest.aspx