Most of the time, Microsoft's public declarations are pretty easy to parse. A bit of pre-announcement here, a touch of FUD there, with the odd dollop of feel-good waffle thrown in for good measure. Occasionally, though, it produces what can only be called a googly – not to be confused with a Google – with announcements like this one about adding support for ODF in Microsoft Office:

When using [Microsoft Office 2007] SP2, customers will be able to open, edit and save documents using ODF and save documents into the XPS and PDF fixed formats from directly within the application without having to install any other code. It will also allow customers to set ODF as the default file format for Office 2007.

At first sight this seems incredible – a complete U-turn from Microsoft. But it's important to remember that we have been here before:

Expanding on its customer-focused commitment to interoperability, Microsoft Corp. today announced the creation of the Open XML Translator project. The project, developed with partners, will create tools to build a technical bridge between the Microsoft Office Open XML Formats and the OpenDocument Format (ODF). This work is in response to government requests for interoperability with ODF because they work with constituent groups that use that format. In addition to being made available as free, downloadable add-ins for several older versions of the Microsoft Office system, the translation tools will be developed and licensed as open source software. The translation tools will be broadly available to the industry for use with other individual or commercial projects to accelerate document interoperability and expand customer choice between Open XML and other technologies.

As we now know, those “translators” were pretty useless, and so one concern has to be that Microsoft's ODF support in Office will be less than perfect. But even if they are, the signal that Microsoft is sending to users is still extremely strong: that ODF is supported, and that if you use Microsoft Office, you can happily adopt ODF as the default format. If it turns out that these statements aren't true, then customers will be unhappy, and the blame will lie squarely with Microsoft. So I don't think the imperfect support argument is very strong.

What about this, then?

Microsoft will join the Organization for the Advancement of Structured Information Standards (OASIS) technical committee working on the next version of ODF and will take part in the ISO/IEC working group being formed to work on ODF maintenance.

As I've written elsewhere, I see increasing signs of new Microsoft approach to open source, which involves loving applications to death, while undermining GNU/Linux. The idea might be to lull the wider free software community into a false sense of security while digging away at the foundations, so that one day open sources apps find themselves running mostly on Windows, with Microsoft in the driving seat.

That's more of a long-term threat, albeit one that the free software world needs to be aware of. So, just for the sake of argument, let's assume that Microsoft is sincere, that it really will offer proper ODF support in Office, and that it really wants work with rather than against the OASIS technical committee: why might that be?

I'm sure that one reason it feels able to make this move is that as Matt Asay astutely points out, for the corporate sector, the game has moved on:

People are agog that Microsoft has announced support for Open Document Format (ODF), but I'm not sure why. This was a foregone conclusion once Microsoft figured out how to move lock-in above the file level to the content network.

In other words, to Sharepoint.

Microsoft has been hell-bent on getting enterprises to dump content into its proprietary Sharepoint repository, calling it the next Windows operating system. I call it the future of Microsoft lock-in.

Microsoft doesn't need to zealously guard file formats anymore. It already owns the next few decades of lock-in, and many enterprises are willy-nilly dumping their content into Microsoft's proprietary repository at a pace and in a manner that is as potentially destructive for those enterprises as it is beneficial to Microsoft's income.

Matt is absolutely right to finger SharePoint as one of the least-appreciated threats to open source. But I also think other important factors were at play in this latest decision – after all, not everyone uses SharePoint, and so there is still a considerable downside for Microsoft.

I think the answer in part lies in the recent series of defeats that Microsoft has suffered at the hands of the European Commission. These have been about interoperability, or the lack of it, and there are other investigations underway that also involve this issue. Maybe the the fines that the company has had to pay have finally reached the level – one involving nine zeroes - where even Microsoft is forced to acknowledge them and do something about it. Adding proper ODF support should head off much of the criticism it is facing in Europe.

Finally, it's also interesting to note that criticism of Microsoft's file formats was expressed in a rather different way recently, during the bitterly-contested ISO vote on OOXML. Although Microsoft's machinations mean that it looks like OOXML will be approved, the voting pattern delivered an undeniable slap in the face for the company, as others have noted:

In an ominous sign for Microsoft (NSDQ: MSFT)'s growth prospects in emerging regions, countries that represent the world's fastest growing tech markets voted against accepting the company's latest Microsoft Office document format as an international standard.

Brazil, India, and China, which together count for more than a third of the world's population, all voted against Office Open XML in voting last week before the International Organization for Standardization (ISO). Russia was the only member of the so-called BRIC nations to vote in favor of ISO ratification for OOXML.

As Microsoft well knows, these markets are where most of the future growth can be expected. If they are bent on ODF adoption regardless of ISO ratification for OOXML, Microsoft will effectively be shut out of the hottest markets unless it builds some bridges (one of its favourite metaphors at the moment).

Supporting this view is the fact that Microsoft's latest announcement also includes news support for the less well-known (in the West, at least) Chinese national document file format standard, Uniform Office Format (UOF):

Microsoft is also committed to providing Office customers with the ability to open, edit and save documents in the Chinese national document file format standard, Uniform Office Format (UOF). The company does so today by supporting the continued development of the UOF-Open XML translator project on SourceForge.net, and will take additional steps to promote the distribution and ease of use of the translator. As UOF develops and achieves market adoption in China, Microsoft will distribute support for this format with Office to its customers in China.

So, what's your view? Has Hell frozen over?

Glyn Moody writes about open source at opendotdotdot.