"This doesn't make us want to go back to Office, [but] it encourages us to use both formats," said Danny J. Wall, a network engineer at Health First Inc. in Rockledge, Fla.

For the past two years, Health First has been slowly shifting its 5,000 desktop users from Office 97 to OpenOffice.org, an open-source application suite. Using OpenOffice is reducing the health care provider's costs and has required less retraining of employees than upgrading to Office 2003 would have, Wall said.

By default, OpenOffice stores files in the Open Document Format for Office Applications, or ODF. But it can also import and export files in earlier versions of Microsoft's Office formats. Because most of Health First's files are still in Microsoft formats, and in recognition of Office's continued dominance at other companies, Wall said he doesn't strong-arm employees to start saving files in ODF.

As a result, he said, "nobody says 'we just can't use OpenOffice,' because we don't force it on anyone."

Dave Jenkins, chief technology officer at Backcountry.com, an online retailer in West Valley City, Utah, said he wasn't very impressed by Open XML's adoption as an Ecma standard. "In the long run, I think everyone will go to XML, but I don't think they'll go to Microsoft's XML," he said. "If something is going to be open, it has to be all the way open."