If you've been following the tech press at all, you've no doubt heard the term "Windows Blue," referring to the internal code name for the next version of Microsoft's desktop-and-or-tablet operating system. I'm not much on rumors and leaks, preferring to get solid info from the horse's mouth. My Microsoft contacts not only won't comment on this matter, but studiously avoid using the term "Blue" in email.

Recent evidence, however, makes a pretty compelling case that Windows Blue is real. Most convincing of all is a leaked installer for a build of the operating system called Windows Blue Build 9364. Ostensibly coming from a Microsoft partner, the build started appearing on file-sharing services like BitTorrent on March 24, and was first mentioned on a post by a site called Windows 9 Beta.

[Update: Microsoft has now officially acknowledged that it's working on projects codenamed "Blue," without providing any product details. The info came in a post on the Official Windows Blog by Frank X. Shaw, Corporate Vice President of Corporate Communications at Microsoft. Shaw does note that it's unlikely that the released new version of Windows will actually use the word "Blue" in its name.]

So what is Windows Blue? The first thing to know—assuming that what we've seen so far isn't an elaborate hoax—is that it's not going to be the kind of complete re-think of the operating system that Windows 8 was. By all indications, Windows Blue will be an enhancements and refinement release. This makes sense, when you consider that that was the strategy for Windows from Windows 95 all the way to Windows 7.

This strategy also jibes well with another release strategy the rumor mill has turned up: That Microsoft will be releasing versions of Windows every year, rather than every three years. This more Apple-like approach lends itself to more incremental, less-drastic overhauls with each new release.

Microsoft executives have hinted at this more frequent upgrade schedule, and word on the street is that Windows Blue will launch as early as this summer or fall. As with a lot of the inside dope on Blue, this tidbit comes from Microsoft-watcher-extraordinaire Mary Jo Foley, who put the pieces of evidence together in a piece on Redmondmag.com called Can Microsoft Speed the Pace of Windows?

An analysis of the leaked code by MSFTKitchen suggests that Blue will come in flavors for all existing Windows editions, including RT and Server as well as desktop personal and professional.

One question that remains is whether we'll see months of public preview versions like we got with Windows 7 and 8. Another involves naming: There's no way to know at this point whether the product will be named Windows Blue, Windows 9, or something else. Microsoft may not even have nailed this down definitely itself yet.

What's in Windows Blue?

So there's some release framework, but what changes can we expect in the software itself? Based not only on the leaked pre-release code, but also on videos from internal company meetings, most notably one leaked by MSFT Kitchen, we can conjecture on what we can expect to see in Windows Blue/Windows 9.

More Touch. The above-referenced video emphasizes new touch capabilities in the OS, showing detailed drawing that becomes possible with the improvements. According to the Verge's Tom Warren, a new swipe up gesture will access app lists in both new and desktop interfaces.

More Snapping Options. "Snapping" is Microsoft's term for displaying more than one running app at a time on the screen—something not even possible with the leading tablet, the iPad. With Windows 8, you can display a secondary app in a reduced view that takes up a quarter of the screen alongside your main app. But with Blue, you'll get more options, such as displaying each in an exact half of the screen, or even four apps in vertical quarters.

New Included Apps. Leaked screenshots of the alleged Windows Blue build show a few new default new-style apps to complement Mail, People, Calendar, and the rest. An Alarm and Sound recorder show up, as does a tile with numbers, presumably a calculator.

Smaller Start Screen Tiles. Windows 8 only offers two tile sizes for its Start screen, a large square, and a rectangle twice that size. With Blue, it looks like you'll be able to use smaller tiles a quarter the size of Windows 8's squares. This should help if you have lots of tiles that lend themselves to organization in groups.

New Charm Bar Capabilities. Windows Blue's Charm bar will offer more direct customization than Windows 8's, in which you often have to go to the desktop Control Panel to make the change you want. Users will be able to further customize the Start Screen from a "Personalize" choice, which will let you swap out the background, edit background colors, and edit accent colors directly from the operating system's sidebar. Another new Charm option seems to be improved search capability.

Internet Explorer 11. Window 7 users only recently got an update to IE10, the browser that ships with Windows 8, which vastly increases support for HTML5 and speeds up browsing. The leaked build of Blue shows yet another update for Microsoft's browser, which will no doubt make further advances in these areas. PCWorld's Brad Chacos has uncovered one more new capability in IE11—tab syncing. This only makes sense, since it's a feature IE's competitors have had for over a year.

Touch Improvements. Windows 8 is already replete with touch input capabilities suited to tablet computing. But Blue looks to go beyond this, as the video linked above shows.

SkyDrive syncing. The new-style Windows 8 SkyDrive app doesn't offer syncing the way the desktop and Windows 7 versions do. The Blue code suggests that this lack of ability will be remedied in the new version.

Blue Skies for Windows?

It's certain that more features and tweaks will show up in the coming months, so this list is far from exhaustive. And as you can see, these new features aren't drastic re-thinkings of basic OS elements, but rather enhancements and improvements to Windows 8.

As with any future release, especially one that's not even acknowledged by its maker, many questions remain about Windows Blue, not the least of which is pricing. Will those who just bought Windows 8 or a machine running it have to pay for an update already this summer? If so, we can hope it's at least priced more like a $20 Mac OS X upgrade rather than a $200 Windows OS upgrade.

If you're not familiar with Windows 8, a laundry list of Windows Blue improvements won't mean much to you, so be sure to read our review of Windows 8 to get up to speed.

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