Definitive word on the implications of the i4i judgment; see the full post for more details
We do not anticipate any interruption in the availability of Word or Office 2007. Additionally this ruling has no impact on the scheduled availability of the 2010 Office version which is planned for the first half of CY2010.
Current users are not affected. If you are using the custom XML tags in Word 2003 or 2007 (these show up in Word as Pink Tags around tagged content), you are free to continue doing so with the products you have already purchased.
Open XML standards (all ECMA and ISO versions) are not affected. Even if Word's specific implementation of custom XML support does infringe the i4i patent (which Microsoft does not believe to be the case), i4i has never claimed that its patent is essential to the OXML standard.
Content Controls of Word (screen shot below) are not affected. In Word 2007 and Word 2010, this is a common method of binding document content to data stored in a custom-defined schema within a document.