OpenDocument (OASIS Open Document Format for Office Applications) has been accepted as an ISO standard (ISO/IEC 26300). It has been reported that the voting has had a great participation and not a single negative vote (albeit a few abstentions).
This is a great step towards an open standardization of document files. ODF is already used by FOSS office bundles like KOffice and OpenOffice.org and individual applications like the word processor AbiWord, spreadsheet Gnumeric and desktop publishing Scribus. There are also reports of a stable (but unreleased as of yet) plug-in for MS Office to be able to work with OpenDocument files.
*[ISO: International Organization for Standardization