Windows 8 looks set to impose a steep learning curve on future users, as the new operating system breaks dramatically with the conventions of previous versions and adopts a user interface more in keeping with Microsoft's Windows Phone platform.

We tested the Windows 8 Consumer Preview on a HP TouchSmart 520 all-in-one PC, and found that while the new Metro-style user interface has much to recommend it, it also feels rather constrained and limiting when compared with the desktop of Windows 7 and earlier releases.

The home-screen is a whole different world to the traditional Windows interface

The impressions gleaned from our initial hands-on with the Windows 8 Consumer Preview are that many users are likely to be baffled by the Metro-style user interface, and it could take a long time for most people to get used to it, as it introduces a completely different way of working.

Overall, Microsoft has not changed the look and feel of Windows 8 much since the Developer Preview that we tested out the firm's Build conference in September.

The main Start screen still consists of a set of blocky coloured tiles that represent applications or functions, such as email, messaging, web browser, and photos. As before, the tiles are 'live' meaning that they show status updates such as notifications of new emails, and touching a tile or clicking on it with a mouse opens the application full screen.

For users of Windows Phone, all this will have a certain amount of familiarity, as the Metro-style look is largely inherited from Microsoft's smartphone platform. For pretty much everyone else, the change is likely to be a jarring experience.

It is not even immediately clear how you access settings using the Metro interface. This is partly accomplished via what Microsoft terms ‘charms' - pop-up tools that appear if you swipe or move your mouse to the right edge of the display (see screenshot).

In fact, the whole Windows 8 experience is designed around giving the user access to their key information - email, messaging, contacts, social networking - directly from the main screen.

For those wanting to use existing Windows applications, there is still a Desktop that can be accessed by a tile on the start screen. It looks very like the desktop of Windows 7, but is a largely emasculated version with no Start menu and nothing more than the Recycle Bin icon showing.

It appears that applications must be launched from the main Start menu, with current applications opening in the Desktop rather than as a Metro-style app. Built-in Windows tools such as the Computer Management console can be found if you look for them, and these run in the Desktop.

The new-look Metro applications have a deliberately sparse appearance, and are designed to fill the entire screen.

Using these can also be confusing at first, as many of the controls and menus that Windows users are accustomed to are completely absent, and you often have to resort to searching for the charms or context-sensitive menus that pop-up from the bottom of the display.

Still, it's clear Microsoft has understood that with mobile devices, chiefly smartphone and tablets, set to dominate the future of computing, the Windows 8 system needs to meet this trend.

The use of the live tiles, as on the Windows Phone platform, is a slick, innovative system, and many users may, having got over the initial shock of the new system, quickly find themselves happily using the new interface without too much difficulty.

Metro-style website display in IE10 on Windows 8

We also found installing the Windows 8 Consumer Preview more challenging than with earlier pre-release versions of Windows. Based on previous experience, we expected the best route to take would be to create a bootable DVD and perform a clean install from this.

However, we soon ran into problems as our test system had Windows 7 pre-installed, and Windows 8 declined to install itself to any of the available partitions, stating that the "selected disk has an MBR partition table. On EFI systems, Windows can only be installed to GPT disks."

GPT, or GUID Partition Table, was introduced as part of the Unified Extensible Firmware Interface (UEFI) initiative to replace the ageing PC Bios firmware.

To cut a long story short, we were forced to use the Diskpart tool from the command prompt to delete each existing partition, then use the same tool to convert the disk to GPT before creating a new partition to accept Windows 8.

After this, Windows 8 installed, but the clean install has some drawbacks which we found out too late. We had lost the drivers for the touchscreen hardware, among one or two other things, and Windows 8 was unable to find suitable drivers to do the job.

We managed to locate the necessary drivers on the support section of HP's website, but the install file checks which version of Windows you are running and will not proceed on Windows 8.

We hope to find a solution soon and provide a fuller report on Windows 8 running on the HP Touchsmart 520. In the meantime, we sincerely hope that Microsoft provides a better upgrade experience for users than this when Windows 8 finally ships.

Windows 8 may not be available until 2013, according to an analyst quoted by Reuters, despite Microsoft's many statements that the software is expected to be available around the middle of 2012.

The analyst, Michael Cherry of Directions on Microsoft, said that the inevitable delay between the OS being released to manufacturing (RTM) and when vendors will have it ready-loaded on new machines could easily push availability of Windows 8 into early 2013.

This analysis would seem about right to my mind, given that Microsoft has only recently made available a developer preview version of Windows 8, and has yet to deliver a single beta version.

Looking back at the progress of Windows 7 as a guide, Microsoft first previewed this in October 2008, before releasing the first beta in January 2009, hitting RTM in July, and general availability in October.

Given that Windows 7 was a relatively minor update of Vista, while Windows 8 introduces some quite radical changes to the user interface and APIs, I would expect its development timeline to take at least as long, which makes mid-2012 seem somewhat optimistic to deliver the final release.

Microsoft could still surprise us, but I now expect to see a beta in January (probably at CES in Las Vegas), with RTM possibly coming in late summer at the earliest. So we might just see machines shipping by Christmas 2012, but don't bank on it.

Windows 8 is not expected to ship until sometime in 2012, but we managed to briefly try out the Developer Preview version of the software at Microsoft's Build conference.

The platform is quite clearly a major change over what has gone before, and people familiar with the Windows desktop could be forgiven for feeling somewhat lost at first, as the Metro interface works in a totally different way.

However, we think consumers will find a lot to like in Windows 8, particularly the way it provides easy access to data, and makes it simple to perform tasks such as updating social meda sites.

Metro obviously has a lot in common with Windows Phone 7, Microsoft's smartphone platform, the main Start screen consisting of tiles to represent applications, rather than the start menu of Windows 7 and earlier.

As with Windows Phone, the tiles are typically 'active', showing if you have new messages or emails, for example. Also like Windows Phone 7, touching the tile launches the application, and the tiles can be rearranged as desired and even bunched together into named groups.

The Metro-style apps are also a big change over the way Windows applications look now. Typically, these fill the screen and lack any of the borders and controls we are used to seeing, in a deliberate attempt to emphasise the content of the application.

As a result, apps tend to look very spartan, and the use of bold colour lends a kindergarten feel to the whole experience.

User interaction is also different, and designed to accommodate touch input, stylus control and keyboard and mouse input. Controls and other tools are typically found by swiping an edge of the screen.

A swipe to the right brings up what Microsoft calls 'charms' - common functions such as search and share, devices and settings - while a swipe to the left flicks through open Windows in the same way as alt+tab on Windows 7.

In fact, if you have a keyboard, using alt+tab performs exactly the same function, showing how Microsoft has blended existing Windows functionality with the new-style user interface.

However, the old Windows desktop has not entirely gone away. The Desktop app tile on the Start screen brings up a desktop very similar to that of Windows 7, and it is here that existing Windows applications run.

Switching between the two interfaces can be a jarring experience, though, especially on a tablet where the standard Windows controls are just too small to reliably hit using a touch screen, showing that the mouse is not redundant just yet.

The browser in this release of Windows 8 is a preview version of IE10. In Metro mode, this uses the whole screen to display a web page, and touching the top or bottom of the screen provides access to the back button or address bar. It is also available in the Desktop app, where it behaves more like IE9 on Windows 7.

One major feature of Windows 8 is the integration with cloud services, particularly Windows Live SkyDrive, which is used to synchronise data across multiple devices so that all contacts, photos, emails and other information is available on whatever unit the user happens to have with them.

The new-style apps in Windows 8 can also share data much more easily than in current versions of Windows, allowing you to email a picture to a friend directly from a Flickr or Facebook application with a single gesture, for example.

Overall, we felt that the Windows 8 Developer Preview provides a much better experience on tablets than existing versions of Windows, although getting used to the new interface could prove a steep learning curve for some.

Finally, this new platform seems heavily consumer-focused, to the extent that business users may be reluctant to adopt it, at least for the foreseeable future.

ANAHEIM: Microsoft has handed out a Samsung tablet running Windows 8 to all developers at the Build conference in Anaheim to help kick-start work on new applications.

The Samsung tablet is unmarked, and the box proclaims it as developer prototype hardware. It features an impressive 11.6in 1,366x768 touch-screen display, and weighs about 900g with a slimline design at just 12.9mm thick.

The tablet is based on a 1.6GHz Intel Core i5-2467M dual-core processor, with 4GB of DDR3 memory, a 64GB SSD, and support for 3G mobile broadband and Wi-Fi.

The unit has a microSD slot, a single USB port and micro HDMI connector. Microsoft is also providing developers with a Bluetooth keyboard, stylus and mini docking cradle that adds an extra USB and HDMI video output, plus Ethernet for a LAN connection.

The tablet feels very responsive, and is easily a match for rival devices such as Apple's iPad or the various Android-based tablets. However, battery life could be a shortcoming, as the indicator went down noticeably during our brief hands-on test.

Microsoft wasn't giving any details on when this tablet might go on sale, but it is obviously a taste of what to expect with Windows 8 hardware.

Among the intriguing snippets that Microsoft divulged about Windows 8 at its Build developer conference is that the platform will be able to run from a USB memory stick.

The Windows To Go feature is being pushed as a useful tool for companies that might otherwise deploy a virtual desktop to some workers, as it is expected to cost about $50 per seat, said Iain McDonald, director of programme management for Microsoft's Windows Core Group.

Other new features are more interesting, especially to roaming users with a laptop or other mobile device.

Microsoft said that Windows 8 is more network-aware than older versions, and can determine which network connection offers the most bandwidth, choosing Ethernet when docked, for example.

The software can also make more intelligent use of mobile wireless connections, pausing Windows Updates when the user roams onto a costly metered 3G broadband connection, and downloading only thumbnails of images rather than the full size.