Microsoft seems to be betting that screen technology in the next few years will be migrating to AMOLED technology. This is why the new Windows Phone 7 Series device sport a very black looking UI as AMOLED screen use less power showing black thus better battery life. This power advantage comes from the screen not using as much power when displaying black areas of the screen. Kinda the same way a light bulb uses less powere when it is off…

However it seems that Office users users will not enjoy this battery life savings as the email display be default had a white background. This is presumably due to the improved readability of back on a white background as opposed to white on a black background.

Source: Pocknow.com GDC: Microsoft is Betting on AMOLED Screen Display on Windows Phone 7 Series

According to pocketnow.com some details have just been released at the Game Development Conference (GDC) about Windows Phone 7 series sceen configurations. Microsoft have said that Windows Phone 7 Series will support 2 resolutions (at least one is 800 X 480 WVGA) but it will only support 1 aspect ratio. This is really good for developers as they no longer need to spend as much time developing their mobile application to work across difference devices. Instead they need to just make it look good on one aspect ratio and the device will automaticlly scale the application to fit on the screen. Somewhat like the iPad however its aspect ratio is different to the iPhone so applciation that are expanded will unused screen on the sides so as to not distort the application.

Source:GDC: Windows Phone 7 Series: 2 Screen Sizes, 1 Aspect Ratio