After months of pre-release versions, cryptic announcements and – lest we forget – interminable flame-wars over the looming death of the Start menu, Windows 8 is truly bearing down on us all. Microsoft’s marketing blitz – estimated to cost a cool $1 billion – is well underway, with flashy teaser trailers cropping up on Youtube and a rock-bottom upgrade price for current Windows users to incentivize the switch.

One thing’s for sure at this point: this is not just a cosmetic upgrade. That trailer makes it quite clear: this is Microsoft’s bid to own the next ten years of home computing. Tellingly, to my eyes, nobody touches a keyboard or mouse at any point in the spot. Windows 8 is all about touch interfaces and that other ideal of consumer IT circa 2012 – that of unifying all your devices, from the desktop to the games console to the smartphone, with an OS that has a finger in all of them.

http://www.youtube.com/watch?feature=player_embedded&v=i1GNDs7DCTw

With the dozens of devices due to ship the morning after launch, tooled up with Windows 8, computer and mobile device makers have got the message. The new OS has been read as a license to break with the classic desktop and laptop form factors.

At the more conservative end of the market, there is a new focus on all in one computers. Heavyweight PC companies from HP to Asus have offered multi-touch screen PCs for a while, but Windows 7 did not provide much in the way of native support. All that is changing with 8, which offers both the new ‘modern’ UI designed ground-up for gestural control, and a revision of the classic Windows layout retrofitted for touch control. Assuming Microsoft can get its drivers in order for the 26th, these existing touch-screen PCs will get a lot more fun overnight for those users prepared to take the plunge and upgrade. Meanwhile, Dell is offering new touchscreen versions of its Inspiron and XPS One all-in-one machines, and various other players in the PC world – great and small – are looking to grab a share of the touch-enabled market.

More intriguing are hybrid designs like Sony’s Tap 20, which splits the difference between the AIO and tablet formats. It’s not as portable as an iPad, with a 20-inch screen, but it’s mobile enough for any home use, can sit flat on a table or propped up on a flexible stand, and comes with its own wireless keyboard/mouse combo for ‘traditional’ computing purposes. Factor in features like SmartGlass, which turns Windows 8 devices into wireless controllers for an Xbox, and the Tap 20 (or machines like it) could become genuine, if quirky, competitors in the home PC market.

Sony Tap 20

This, hopefully, is the shape of things to come. Windows 8 does the heavy lifting in terms of ensuring cross-platform compatibility and interaction, even in its cut-down but still powerful ARM version, Windows RT. It makes this possible first of all through a powerful set of common development tools and standards (including the integrated ‘charms’, which organise features common to many different apps), and secondly through intelligent use of networking, cloud computing and related technology. With that infrastructure in place, the way is open for hardware and software designers alike to find slicker, quicker or just plain crazier ways to use a computer.

The biggest surprise in all this is the sight of Microsoft being active, rather than reactive. It would be easy to say that it is trying to beat Apple on the latter’s home turf, and certain features – notably the ‘walled garden’ Windows app store – are clearly inspired by the closed, harmonious ecosystem that Apple made such a compelling selling point, especially on its mobile devices. But Windows 8 does something that Apple, with its total vertical integration of software and hardware, can’t: it gives license to PC manufacturers to be bold and innovative themselves … and not before time.

For the next month or two, it will be Apple for once that looks like the lumbering behemoth, especially following the lukewarm reception to the iPhone 5.  To press the advantage, Microsoft will have to get Windows 8 onto enough PCs to make a difference, and lure forward-thinking app developers out of their Apple- and Android-dominated mindset.