This story will go ballistic. It's coming over right now like the biggest change at Redmond since the company finally "got" the Internet. But the details are all going to be in the coded press announcements going on right now.

The Register leapt in with "Microsoft goes open source - almost" but although there's some mention of open source in there, it looks like that isn't the main thing going on here.

Microsoft's own press release, and Ballmer in the press conference, are pretty clearly talking about opening up communications APIs not code.

"We will document all of the application programming interfaces of all the communications protocols used by Microsoft products and developers would not need to take a licence," said Steve Ballmer, quoted in Clomputer Weekly.

That is new. But a lot of this will be spin. This is a strategic direction change, but in a direction which has been obvious to everyone outside Microsoft for some time, and - I would have to be - still a grudging change that is as limited as Microsoft can manage under the circumstances.

Microsoft's main promises are
"(1) ensuring open connections;
(2) promoting data portability;
(3) enhancing support for industry standards; and
(4) fostering more open engagement with customers and the industry, including open source communities."

Microsoft has been publicly claiming to support every single one of those for at least the last ten years.

I'm betting that the underlying strategy is the WAMP not LAMP thrust we noted here earlier.