Microsoft Windows Phone 7 release date 21 October

Microsoft officially launched Windows Phone 7 today and the Redmond giant has showcased a number of devices featuring the new OS.

In the UK, a total of six phones will feature Windows Phone 7 and they will be available in time for Christmas 2010.

These include the HTC 7 Mozart, Samsung Omnia 7, HTC 7 Trophy, LG Optimus 7, HTC HD7 and the Dell Venue Pro.

All except the Dell will be released on 21 October on various providers.

The HTC 7 Mozart will be available on Orange and the HTC 7 Trophy on Vodafone, while the Samsung Omnia 7 will be on Orange, T-Mobile and 3. The HTC HD7 will be on O2 and the LG Optimus 7 will be on Vodafone.

As for the Dell device, no providers were confirmed at the time of publication.

"They [the phones] are all beautiful the hardware and the way the software is always delightful across each and every one of these experiences," said Microsoft chief executive (CEO) Steve Ballmer, during a press conference in New York.

The firm believes it has built "a different kind of phone," Ballmer claimed.

"The differences in the Windows Phone are as much about what you are going to do with the phone as with how you do them," he explained.

"We wanted the Windows phone to be delightful across a range of different hardware devices and across a range of different applications and experiences. We wanted it to be that way for the consumer and the developers."

Ballmer also pointed to the personal aspect of the OS, which has been designed to be highly customisable.

"We also stress the notion of having the phone be wonderfully mine.' Everybody should be able to say I can represent me on this device,'" the chief executive said.

TV personality Stephen Fry made a surprise appearance to help launch the phone, strictly appearing as "an amateur," he told delegates.

"I made no secret of my dislike of Microsoft over the years," he said. "Microsoft were gray and were featureless. They forgot even the grayest number cruncher in an organisation is a human being first."

"They now, I think, get it. They understand that people ... are human beings first."

He said the Windows Phone 7 OS was simply fun to use and he was pleased to hear the word "delightful" being used in the marketing spiel for the Microsoft product.

Fry said the OS has its deficiencies, but that is no different from the Apple iOS.

"I'm not a monotheist. I want biodiversity in this market. The more players there are in the market, the more creative it becomes," he added.

"They [Microsoft] really have changed their outlook."