Building on the momentum from its reveal at Mobile World Congress, Microsoft is stressing the importance of games to its Windows Phone 7 platform, which has full integration with the Xbox Live platform including avatars, gamer tags and achievements.

"Games is a first class citizen. It's a key experience for Windows Phone 7," stated Ron Pessner, general manager, Xbox Live mobile.

At GDC, the company's big announcement was the launch of XNA 4.0 Game Studio, the latest version of its development environment for Windows Phone 7 Series, Xbox 360 and PC.

Gunning for 3D

This is particularly important as it introduces optimised Direct3D APIs for hardware accelerated graphics for Windows Phone 7 devices.

Microsoft has been highlighting this with game demos including The Harvest from Luma Arcade and Battle Punks from Gravity Bear and Mythos Labs. Both were created in around three weeks; something Pessner stressed demonstrated the efficiency of using XNA.

"We think it will enable developers to make better games faster," he said. "Productivity is a major focus for XNA 4.0 Game Studio."

Another key feature is the cross-platform nature of development, with around 90-95 percent of code reckoned to be reusable across Windows Phone 7, Xbox 360 and PC. Changes are generally focused around input and screen resolution and orientation.

"There have been over one million downloads of XNA Game Studio so there are a lot of people who are familiar with the tools. We're really excited to see what developers will come up with for Windows Phone 7," Pessner said.

And with the likes of EA Mobile, Gameloft, Glu Mobile, Capcom and Oberon also signed up to provide games for the holiday 2010 launch, it seems both the indie and major elements of the market will be well covered.