Microsoft has revealed the "Windows Phone 7 Series" at Mobile World Congress, the next-gen version of its Windows Mobile platform. CEO Steve Ballmer announced the launch during a press conference which will bring together both Xbox LIVE games and the Zune music and video experience.

"I'm proud to introduce Windows Phone 7 Series, the next generation of Windows Phones", says Ballmer in the press release. "In a crowded market filled with phones that look the same and do the same things, I challenged the team to deliver a different kind of mobile experience. Windows Phone 7 Series marks a turning point toward phones that truly reflect the speed of people's lives and their need to connect to other people and all kinds of seamless experiences".

Microsoft says the Windows Phone 7 Series "takes a fundamentally different approach to phone software". On the Start screen, what Microsoft calls "dynamically updated live tiles" offer real-time content while every Windows Phone 7 Series phone will come with
a dedicated Bing hardware button.

The platform will be formed around "Windows Phone hubs" made up of "People" with Facebook integration, "Pictures", "Games" (which will offer an official Xbox LIVE experience on a phone), "Music + Video" with Zune services built-in, "Marketplace" for apps and "Office" for productivity.

As far as hardware goes, Microsoft says partners have already started building phones but the first phones won't be in stores until Christmas 2010.

Companies who've said they will offer Windows Phone 7 Series devices include  AT&T, Deutsche Telekom AG, Orange, SFR, Sprint, Telecom Italia, Telef√≥nica, Telstra, T-Mobile USA, Verizon Wireless and Vodafone as far as mobile operators go and Dell, Garmin-Asus, HTC, HP, LG, Samsung, Sony Ericsson, Toshiba and Qualcomm as far as manufacturers go.