This is the full Unreal Engine 3, all 1 million + lines of C++ code. The art assets of the Citadel demo are I believe the same as in the Flash demo, which were

This is the full Unreal Engine 3, all 1 million + lines of C++ code. The art assets of the Citadel demo are I believe the same as in the Flash demo, which were optimized for a more mobile-friendly and touch-friendly environment. However we also showed a full Unreal Tournament demo running, as I mentioned in another comment, both at our GDC presentation and in the booth where people could play it. That's a full desktop level.