Photo by Mag3737

I've been closely following Microsoft's Open Specification initiative. A lot of people were sceptical, based on MS's long history of using its closed platform to block competitors and the fact that the move was driven by EU legal action. I had hope, mostly because the company has superb third-party developer support in its DNA. Since July I've been actively using the Exchange and Outlook documentation, and it has lived up to its promise. There's been errors and oddities, but no big gaps or censorship that I could detect.

I've only been scratching at the surface though, in comparison the folks on Samba have been battling the Beast of Redmond for secret API information for over a decade. That makes Andrew Bartlett's description of their team's week-long visit to the Microsoft campus all the more astonishing:

We were very surprised by the extraordinary degree of effort that
Microsoft put into this single vendor plug fest. We were given direct
access to the Active Directory product team in Microsoft, plus we had
a team of 6 Microsoft engineers working with us full time for the
whole week
…
They knew the protocols in great detail, and were extremely
helpful in working through test cases (both in their own test suites
and ours) and suggesting testing and debugging strategies.

…
Some of the Microsoft engineers have been actively working with the
Samba code base, particularly our test tools, and had prepared for the
plug fest by doing extensive testing of Microsoft tools against
development versions of Samba4

Microsoft's motivations may not be pure, but this is still massive news. They're offering serious help to any third-party developers who need to interact with their server products. This makes a whole set of products suddenly move from engineering fantasy land to a real possibility. If you've ever had an idea that could benefit from working closely Exchange or Active Directory, dig it out from the back of the drawer and re-examine it. You might find it's more feasible than you think.