When news first broke of the new native file formats coming in Office 2007, doom mongers predicted that it would quickly lead to a yawning communications gulf between those running the new software and those using older versions of Office, with Microsoft milking the situation to encourage upgrades.

Even darker motives were suggested for Microsoft's XML Paper Specification (XPS), a new file format for distributing and archiving documents introduced in Windows Vista. This is a direct stab at killing off Adobe's Acrobat .PDF standard, if you believe the rumours.

Perhaps the cynics were right after all. Microsoft has just made available a comprehensive feature-by-feature guide to the new Windows Vista, information that might prove very useful for those pondering an upgrade to the new operating system.

The catch? It is only available as a Word 2007 document, or in XPS format. There is, of course, a downloadable XPS viewer available for those with time on their hands and, indeed, the user priveleges to install such things, but otherwise you will have to be running either Office 2007 or Windows Vista itself– two products only just officially available – in order to view the document.

Microsoft is often quoted as saying it is committed to industry standards, so why release upgrade information in a non-standard format that virtually none of the intended audience can read? It seems like yet more evidence that the old saying holds true – a leopard's spots are fixed for life.