TechPowerUp delivers word that Battlefield 4 will take advantage of the new DirectX 11.1 API. This could give AMD's Radeon HD 7000 series an edge over NVIDIA's Kepler architecture, which doesn't fully support DirectX 11.1, but the impact is likely limited because DirectX 11.1 is only available for Windows 8.x.
In the words of the technical director behind Frostbite, the underlying engine for Battlefield 4, "We use DX11.1, there are some optimizations in it (constant buffer offsets, dynamic buffers as SRVs) that we got in to the the API that improves CPU performance in our rendering when one runs with DX11.1."
In related news, FUD Zilla writes that Battlefield 4 progress will be platform restricted, this means a player's career and progress can't be transferred between consoles. This is not a change from the past though, it's exactly how it works with Battlefield 3 right now but it may be annoying if you have a Xbox 360 and plan on getting an Xbox One soon.
What this means is for example, if you play Battlefield 4 on the Xbox 360, but later want to transfer all of your career and multiplayer rank over to the new Xbox One that you purchased, you will NOT be able to do so. You will be starting over again on the Xbox One version of Battlefield 4.