You can bet that Microsoft's plan is to merge Windows Phone and Windows into a single codebase.

That will be too little too late and too bloated. They needed the focus of WP7 in tablets and not the legacy.

From what I believe, Windows 8 and Windows Phone 8 will be the same OS which runs the exact same apps, only with different UIs for different screen sizes/aspect ratios. Branding then becomes irrelevant: they are literally the exact same OS. No different to iOS for the iPhone and iPad, or Android running on phones and tablets.

It doesn't have to mean bloat either, assuming Windows sufficiently is modular. Just don't include or load the Win32 subsystem. The ARM version doesn't have backwards compatibility anyway.

Windows 8 should be out within the year, and given that it's an extension of the PC market it shouldn't be too late.

If Microsoft can pull it off successfully, it should hugely improve their mobile prospects by allowing them to use their dominance of the desktop. Buying an application once and having it work on your phone, tablet and desktop (and potentially console) is an incredibly compelling selling point that would overcome WP7's current marketshare problem. It would also make it much easier for Microsoft to introduce features: do it once, and get it on every platforms for free. It's a very forward-looking idea.

There has been no confirmation that W8 and WP8 will be the same OS, and in fact the rumors from quasi-reputable sources have been to the contrary: W8 and WP8 development are currently proceeding separately and WP8 is still CE-based; they want to eventually merge the kernels but that is planned for further out, Windows 9. (though I'd imagine whatever plans they have for that far ahead are tentative and probably open to heavy revision once they get around to actually working on

(a more realistic and interesting possibility though is that the new Windows Runtime/Jupiter framework in W8 will be ported to WP8/CE, which could make it easy to write (new) apps that work on both. There is some evidence of this in the leaked W8 builds as they include support for phone dialing.)

Yeah, I might have accelerated the timeline a bit.

Even so, I think it's clear that they're going in the direction of merging code-bases, and I'm certain that touch-screen Windows 8 and Windows Phone 8 apps will be cross-platform and be based around the same high-level framework. It'd be insanity otherwise.

> Just don't include or load the Win32 subsystem.

Wishful thinking. If you develop a nontrivial app for Windows, you must go down to the Win32 API. e.g. Hardware assisted Video decoding, Direct3D, many COM apis are not at all or not properly available in .net. If you don't load Win32, nothing except simple .NET CRUD apps is going to work.

Sure, for current Windows software.

But all signs are pointing to Microsoft cooking up a new 'native' software framework for Windows 8 that is much closer to what WP7 is today.

The specifics won't be revealed until BUILD next month, but that certainly looks like the direction they're going.

Well, there have been "cross platform" frameworks before, for some definition of "cross platform". But the key here is that it is a _new_ platform.

Why would a developer prefer to use one new platform (Win8 / WP8) over another (MeeGo, WebOS, Bada, iOS)?

The appeal of Windows for developers, for the last 15 years, had been "installed user base" (which is strongly related to backwards compatibility). If you take away backwards compatibility (hence no instant installed user base), why is W8 relevant?

Windows 7 sold 300 million copies in less than 2 years. There's no reason to think that Windows 8 won't match it. That's a huge potential market.

Apple proved that you don't need the largest installed user base to become a success. You just need a user base that's large enough to be sustainable, coupled with decent developer tools and, preferably, a sales channel.

That also presumes there's no backporting, which is another possibility.

> There's no reason to think that Windows 8 won't match it.

Actually, there is reason to think Win8 adoption will be slower - many people were still on XP (a 10 year old OS!) and holding out on upgrading to Vista because it was so bad (perception wise; no comment on any objective measure of quality). So when Win7 came out and was not bad (perception wise), all those who held out were happy to update. It's possible the Win8 updates won't be as popular because Win7 (like XP before it) is good enough that there is no compelling reason to upgrade.

But even assuming it does do 300 million in 2 years - poll your favorite developers; what is the time frame since win7 was out that they are willing to do a "win 7 only" release? (no vista support, no xp support)? My bet would be that maybe some would NOW, but no one would have a year ago.

.NET has been generally available for 10 years now, .NET a part of XP/Vista/Win7 for over 5 - and the vast majority of generally available desktop software is STILL not using it. Why would you believe a new Win8 runtime would be different?

Even Vista had 200 million users after two years. If Microsoft make the same mistakes as Vista (which is unlikely) and it fizzles, Windows sales figures remain mind-blowingly huge.

Why haven't Windows 7-only applications caught on? A major reason is consumer expectations coupled with only a marginal effort required for backwards compatibility for a big increase in market. .NET was a technical back-end change that isn't user-facing, so it competes with legacy code-bases and existing experience.

If Microsoft's new framework fails, it'll be for different reasons.

> Why haven't Windows 7-only applications caught on? A major reason is consumer expectations coupled with only a marginal effort required for backwards compatibility for a big increase in market. .NET was a technical back-end change that isn't user-facing, so it competes with legacy code-bases and existing experience.

And that's reason enough for Win8 applications not to catch on, unless microsoft manages to create a substantial "other" market in the form of phones or Xboxen. Whether or not they succeed, we will have to wait and see.

The Metro UI is.

http://www.youtube.com/watch?v=p92QfWOw88I

On Xbox too http://blogs.cio.com/operating-systems/16412/microsofts-gamb...