Might Microsoft's Midori be 'Cairo' revisited?

My post a week ago about Microsoft's post-Windows operating system, code-named "Midori," elicited some interesting responses -- and a few potential new clues.

My post  about Microsoft's post-Windows operating system, code-named "Midori," elicited some interesting responses -- and a few potential new clues over the past week.

Might Microsoft's Midori be 'Cairo' revisited?To those of you who sent me notes speculating/wondering whether Microsoft's Midori might be a derivative of the Midori Linux effort and/or the Midori lightweight Web browser project, I'll reiterate that I don't believe these other Midori projects have anything to do with Microsoft's Midori.

Microsoft's Midori -- from what little I've been able to glean about it -- is a next-generation Microsoft operating system that is currently in "incubation" -- meaning that it's likely to be launched sooner than a typical Microsoft Research project, but not so soon as to obviate the need for Windows 7 and Windows 8. In other words, we're looking at a new non-Windows operating system to debut some time before CEO Steve Ballmer retires (a date Ballmer has said is nine or so years away), but not before late 2009/early 2010 (the target date for Windows 7).

As I noted last week, my sources have said that Midori has something to do with "Singularity," the Microsoft Research effort to develop a non-Windows-based operating system from scratch. Midori is the realization that Windows as it exists today isn't the be-all/end-all. Microsoft isn't going to continue to deliver updates to its flagship product without thinking ahead as to what might come next.

(For another view on Microsoft's OS plans, see Ed Bott's "Why you'll have a long wait for Microsoft's next OS."

Since I posted my initial blog entry on Midori, I've received a few additional (and unconfirmed) tips. One that was especially intriguing: Midori is another attempt by Microsoft to deliver on "Cairo," Microsoft's distributed, object-oriented operating system that never saw the light of day.

Think this through, the tipster told me. Eric Rudder, the head of the Midori project, is a "Bill Guy," not a "Steve" Guy. If you look at Gates' pet projects that were left unrequited but are still much loved by Microsoft's Chairman, Cairo has to be high-up on that list.  (Remember Gates' "information at your fingertips" vision? That's what Cairo -- and more recently, the ill-fated WinFS, were all about.) Who better than Rudder to attempt to realize Gates' vision of a truly object-oriented, distributed operating system, the tipster argued?

Will Cairo make a comeback? Not surprisingly, Microsoft isn't commenting. But whether Midori is or isn't Cairo minus the Egyptian codename, it is key to Microsoft's future.

As Apple and other operating-system developers have learned over the years, you can only patch a war-horse for so long. At some point, you need to start fresh. That said, phasing out support for a 1-billion-Windows-PC-strong user base is not a project Microsoft will take lightly. As company watchers know -- despite its well-documented compatibility challenges with Windows XP and Windows Vista -- Microsoft isn't a company that underestimates the importance of app compat.

Microsoft has to be thinking long-term about what kind of operating system will supersede Windows.  I, for one, won't be surprised if Midori still ends up looking more like Windows than not.

What's your bet? What will Midori look like?