It has been long rumored that Microsoft was working on a one-handed keyboard for future devices for some time now, and now a leaked Microsoft Research presentation indicates makes it real. The keyboard is clearly designed to accommodate one-handed thumb typing. Instead of using a standard keyboard to type, the keyboard for the arc-shaped design takes a form similar to standard keypad letters. Letters are clustered together by threes into software input buttons.
The arc-shaped keyboard is presented on a HTC Trophy Windows Phone, which is not expected to receive the future Windows Phone 8 update. This may indicate that the arc-shaped keyboard, if it is released, will at least be available with Windows Phone 7.8. Windows Phone 8 is also expected to include extended national keyboards, including a new Korean keyboard design. Considering Windows Phone 8 is the next big update, there is no doubt that it will include the arc-shaped keyboard.