http://googleappsupdates.blogspot.com/2012/10/docs-export-format-change-delayed-to.html
"On September 25, we announced that we would be changing some of the file exporting functionality in Google Docs on October 1 for scheduled release track customers.We recognize that some of our customers would like more time before the change goes into effect. As you may have noticed, that change did not go into effect on October 1. In order to support our customers and help them through the transition, we have delayed the export format change for scheduled release track customers until January 31, 2013.
We recently added the ability to export Google documents to the newer Microsoft Office formats that rely on open standards (.docx, .xlsx, .pptx). To continue adding new features and innovations to Google Docs, we’ll be focusing our resources on exporting to these newer open formats rather than the older, proprietary Office formats (.doc, .xls, .ppt) that were used in Office 97-2003.
Versions included:
Google Apps, Google Apps for Business, Education and Government"