The State of Massachusetts has just published a new draft version of their Enterprise Technical Reference Model (PDF). In the section labeled "TECHNOLOGY SPECIFICATION: OASIS OPEN DOCUMENT FORMAT FOR OFFICE APPLICATIONS (OPENDOCUMENT)" they state
Description The OASIS Open Document Format for Office Applications (OpenDocument) is a standardized XML-based file format specification suitable for office applications. It covers the features required by text, spreadsheets, charts, and graphical documents. The specification was recently approved by OASIS as an open standard. OASIS has also submitted the standard to ISO for consideration as an international standard for office document formats.
Guidelines The OpenDocument format must be used for office documents such as text documents (.odt), spreadsheets (.ods), and presentations (.odp). The OpenDocument format is currently supported by a variety of office applications including OpenOffice.org, StarOffice, KOffice, and IBM Workplace.
They then go on to describe the migration plan over the next two years.
Needless to say, I think this is absolutely terrific for all the reasons I've outlined before.