Just a quick note. I was pointed at this list of file formats on Wikipedia. The document formats list alone is almost 40 items long. My takeaway from this list is all about the richness of innovation in software. The formats are representations of the features in those products. There are really good reasons that software packages have used their own formats in the past. Performance, feature representation, cost of development, etc. Now, with the push to XML you would think that we would see a decrease in the desire to create separate formats due to the promise of that standard. But, go to the Wikipedia list of XML standards and in there are more than a few formats as well.
I am not advocating more complexity, or more diversification of formats. I am noting that there are really good reasons why multiple formats exist and this will be a truism for a long time to come. I am an advocate for innovation in software and the idea that maximizing choice in the marketplace is good for everyone. The fact of the matter is that translation between formats has always been the path to interop (for document formats), and now with XML-based formats that path is even more appropriate than ever through translation.
China wants to create its own standardized XML format...translation will enable interop. Google Docs has its own format....translation will enable interop. OpenOffice has ODF..translation will enable interop (to MS Office, to Google Docs, to IBM Workspace). Adobe PDF is its own format...translation will enable interop.