详见MS的这两份文件：

http://www.microsoft.com/presspass/features/2005/jun05/06-01XMLFileFormat.mspx

http://www.microsoft.com/presspass/press/2005/jun05/06-01OfficeXMLFormatPR.mspx

主要内容是，Office12中XML文件格式将成为缺省格式，Word、PowerPoint、Excel这三个应用都会有完整的XML格式支持。MS还承诺提供Patch供老版本Office使用该格式。

对于其他开发商（者）使用这种格式的问题，人家说道：

Certainly this will make it easier for other developers to use our formats to build solutions that don’t require Office. However, the ability of other technology providers to use the new file format to integrate their solutions with the Microsoft Office System is an important and frequently requested capability by the industry. We feel it’s to everyone’s advantage to respond. Customers also know that the true value of a desktop application is not the format in which data is stored but the full breadth of capabilities offered by that application, along with the quality and security of the user experience that it provides.

我注意到Format前面的Open修饰。这很微妙，因为MS的这个格式是有版权和专利的。不过人家的宣传中说的是Open and Royalty-Free Formats。

MS这么做，当然不单单是文件格式的变迁这么简单，我想更多的应该是出于协同处理和数据管理方面的考虑（Office12里SmartDocument应该会变得更牛吧）。当国内办公厂家还在为格式兼容问题头痛脑胀时，人家已经在很多方面Create the Future了。