A common concern raised by the opponents to the standardization work we're involved in for Open XML has been the idea that there is no way to independently manipulate the documents outside of Microsoft Office. We have been saying that is not the case, but it was going to take time for people to start working with the standard once it was ratified at Ecma as an industry standard.
Go check out OpenXML4J - it is a Java library that allows you to manipulate Open XML files completely independent of ANY office productivity suite. Cool.
If you are curious, at the OpenXMLDeveloper.org site there are other folks posting interesting work as well around the formats. For example, one of the topline stories up there today is about creating an OpenXML spreadsheet in PHP.
For my non-tech readers - what does this mean? It means that the points we have been making about Open XML for the past year are true. It is a standard, is is licensed so that anyone can use it without concern about IP issues. It means that people are doing indpendent implementation work. It means that interop is happening through things like translators and now through other means as well. Good stuff.