Q: Will users of previous versions of Office be able to open and eidt the new Office 2007 file formats?
A: Yes. The new OpenXML file formats are for Word, Excel and PowerPoint 2007. To help ensure document exchange between different Microsoft Office releases, go download and install the Compatibility Pack. The current version is for Beta 2 Technical Refresh.
Q: What versions of Office does it apply?
A: Office 2000, Office XP, or Office 2003. The compatibility pack features will allow the user to open, edit, save, and create files in the OpenXML file formats.
Q: I've been using the beta version of Office 2007 and cannot save a file as PDF format or Microsoft's equivalent XPS format?
A: This capability was removed from the product but is available as a free add-on and can be downloaded here. The add-on also provides the capability to send an email attachment as PDF or XPS.
Q: Is the OpenXML standard compatible with OpenDocument or ODF standard?
A: Yes, see a previous post. Microsoft is sponsoring an open-source project for the development of converters for reading ODF and saving to ODF from Word. Release of the first converter set for October 23 will let Word users open documents saved in the OpenDocument format. By the end of the year, "save to ODF" functionality is expected to be available.