We already broke out the news you're looking for: Each of the Windows Phone 7 Xbox Live-infused games will offer its players 200 Gamerscore points. You'll be able to boost your Xbox rep in significant chunks without having to hunker down in front of a big screen for long stretches. You'll never again have to go so long without hearing that satisfying "Achievement unlocked" sound. The world, as you know it, has changed.
Fortunately, the channel through which you'll access these on-the-go 'cheevos looks like it has loads of promise. The handful of work-in-progress Windows Phone 7 games we were shown today at GDC didn't leave much of an impression -- however, the effortless portability of games between the platforms supported by the recently announced XNA Game Studio 4.0 opens up a lot of possibilities for development on Microsoft's new mobile device.