Unreal Engine 3 comes to Windows RT
Nvidia demonstrated the ability of Windows RT tablets to use the Unreal Engine to create games.
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The specific device shown, the ASUS Vivo Tab RT, is running the Tegra 3 chipset to show a demo of Epic Citadel. The venture to bring Epic's Unreal Engine 3 to Windows RT was a joint project by Nvidia and Epic.
This is a big leap forward for the Windows ecosystem as not only is one of the top game engines now available for developers to begin working with, it is also the full PC implementation. This gives developers unprecedented support for porting PC and Xbox games to a mobile platform, and vice versa.
Sounds like this could also come to Windows Phone soon.
Source: Nvidia Blog