Microsoft has announced the first public beta (testing) version of Windows 7, its next-generation operating system.

The operating system, which is not finished but has been released so that users can test it and report any problems, will be available for public download on 9 January, when it will appear online at www.microsoft.com/windows7. Subscribers to Microsoft’s Technet and MSDN services can download it immediately via those services.

Windows 7 is planned to succeed Windows Vista as Microsoft’s main desktop operating system. Microsoft claims that with Windows 7 it has “improved what customers care about most – operating system basics”.

It claims that Windows 7 starts up and shuts down more quickly, produces fewer alerts, is more reliable and allows for longer battery life on mobile computers. The new system also supports multi-touch gestures, so users with a touchscreen computer can use several fingers to manipulate objects on screen as they would when using an iPhone.

Microsoft CEO Steve Ballmer announced the Windows 7 beta at the Consumer Electronics Show (CES) in Las Vegas. Other Microsoft announcements at the show centred around new partnerships for its Windows Live online services. Dell will start pre-installing some Windows Live services on its PCs in February, while users of the Facebook social network will soon be able to post photos from the site to Live.

Microsoft also announced new features for its Xbox 360 console's Xbox Live service, but the most important of these – a way for customers to change their Netflix movie download queue using a smartphone – won’t help UK customers, who don’t get access to the Netflix service. Microsoft has not yet confirmed whether the second Xbox announcement, of a new 'Xbox Live Primetime' channel that “brings together the best of TV and gaming” will be available in the UK.