I would love to see another Unreal game... but let's make it feel like an Unreal game rather than a normal FPS. The fun of playing Unreal was that when you died it was always ridiculous and your body would go flying all over the place. One could say that it was rather unrealalistic... but that was what made it fun! There is a time and a place for realism in games, but it would be nice to see games make a return to just being fun, exciting, and unexpected.
Electronic Arts will switch from Unreal to Frostbite. The new Mass Effect is going to use Frostbite Engine instead of Unreal Engine.
So... games published by EA are going to use in house engines: CryEngine and Frostbite. Unreal has lost a big client.
The engine was demoed a year ago but was not finalized until recently when they showcased the new demo called "Infiltrator" (3/29/14). Also, the only gaming company to use unreal engine other than Epic is probably Ubisoft. EA & Disney/LucasArts are using Frostbite 3 and Cryengine 3. Microsoft has their own proprietary engine for Halo 4, Valve is developing a new engine for Half-Life 3, and Activision is still using the same Quake engine albeit heavily modified. Square Enix uses their new Luminous engine and Capcom uses the Panta Rhei engine. New engines are usually used by the same developers who created it before they are licensed to other developers, therefore expect another game from Epic for the xbox1 or PS4. Also, most developers prefer using their own engine since it's easier to work with and they are more familiar with it. You can see an example of all of these engines on youtube for comparison. Lots of talented programmers other than Carmack, Sweeney, Yerli, and Andersson.