Newsflash: The UDK licensing site is now open! Signing up as a commercial UDK developer is a very simple process that takes little time to complete. Anyone can purchase a UDK commercial license.

 * Unreal Engine 3's new procedural building system enables users to very quickly create and edit good looking city buildings.
 * UTGame, the example game content included with UDK, has fully transitioned to UDKGame. All content included with UDK (except for skeletal meshes) can now be used by commercial UDK games and applications.
 * Cascaded shadow maps, dynamically shadowed translucency, and improved unbuilt lighting previews have been added to the lighting system.
 * A new map, GDC_FeaturesDemo, is now included with UDK.
 * The perspective viewport now supports depth dependent halos, making wireframe views much easier to read.
 * The new asset consolidation tool provides a simple way within the editor to consolidate multiple assets into one asset.
 * Also included are dozens of upgrades to the Unreal Editor, Unreal Matinee, Unreal Content Browser, and other Unreal Engine systems and tools.