(17) Office Open XML. The “.docx, .xlsx and .pptx” file formats used in the Office 2007 version of Microsoft’s Primary PC Productivity Applications shall implement the ECMA 376 Specification. This commitment shall apply to successor versions of Microsoft’s Primary PC Productivity Applications with respect to IS 29500. This means that Microsoft shall support the relevant standard and provide a warranty as specified in the general provisions in Section B.I of this Undertaking, effective 1 January 2010.

(18) Microsoft shall publicly document Additional Information for the ECMA 376 Specification that meets the requirements of paragraph (15) above. This commitment shall apply to successor versions of Microsoft’s Primary PC Productivity Applications with respect to IS 29500. Microsoft shall provide a warranty as specified in the general provisions in Section B.I of this Undertaking, effective 1 January 2010.

So Paragraph 15 seems interesting:

(15) This paragraph describes how Microsoft shall implement paragraphs (16) to (18) and Section 2.2. Microsoft shall make Interoperability Information available to interested undertakings relative to file formats used by Microsoft Office Word, PowerPoint and Excel that allows third-party Software Products to open, manipulate, save, exchange and share documents created by Microsoft’s PC Productivity Applications without a loss of container structure information or any instructions in the file that describe the document's formatting characteristics. For these purposes, file formats are understood as containers to hold data created by users of those Microsoft’s PC Productivity Applications and information describing associated properties of that data, and the Interoperability Information in the foregoing sentence does not include information about the functionality of these applications or the underlying operating systems that could be used to clone or port Microsoft products in whole or in part.

Now the patent pledge for open source… developers!

Patent Pledge for Open Source Developers

Microsoft irrevocably promises not to assert any Microsoft Necessary Claims against you as an open source software developer ("You") for making, using, importing, or distributing any implementation of the Technical Documentation ("Covered Implementation"), subject to the following. This is a personal promise directly from Microsoft to You, and You acknowledge it is a condition of benefiting from it that no Microsoft rights are received from suppliers, distributors, or otherwise by any other person in connection with this promise. To benefit from this promise, you must be a natural or legal person participating in the creation of software code for an open source project. An "open source project" is a software development project the resulting source code of which is freely distributed, modified, or copied pursuant to an open source license and is not commercially distributed by its participants. If You engage in the commercial distribution or importation of software derived from an open source project or if You make or use such software outside the scope of creating such software code, You do not benefit from this promise for such distribution or for these other activities.
To clarify, "Microsoft Necessary Claims" are those claims of Microsoft-owned or Microsoft-controlled patents that are necessary to implement the Technical Documentation. … Where a software development project has in all other respects the characteristics of an open source project, distribution among the participants of that project of source code developed by natural persons under an employment contract or by natural or legal persons under a contract to develop is not considered to be commercial distribution, and that software development project does not lose its character as an open source project merely because such distribution takes place among participants. Software is deemed to be commercially distributed within the meaning of this promise when the distributor derives revenues in connection with the distribution, such as from subscriptions, updates, or user-based connection fees or from services that are contractually required for a customer to obtain the current version and/or updates of the software product in question.
This promise is not an assurance either (i) that any of the Microsoft-issued patent claims cover a Covered Implementation or are enforceable or (ii) that a Covered Implementation would not infringe on patents or other intellectual property rights of any third party. No other rights except those expressly stated in this promise shall be deemed granted, waived, or received by implication, exhaustion, estoppel, or otherwise.

I wonder how much fun Brad Smith and his colleagues had with this…