According to a recent of post of Johan Andersson, Technical Director of Frostbite at Dice, it appears that Battlefield 4 will indeed prefer AMD's Radeon HD graphics cards, all thanks to its support for DirectX 11.1.
According to his notes, Battlefield 4 will have certain optimizations like constant buffer offsets and dynamic buffers as SRVs, that will improve CPU performance in rendering when running in DirectX 11.1. Of course, this can only be achieved with PCs running on Windows 8 and upcoming Windows 8.1 and give certain edge for AMD Radeon HD 7000 series GPUs as Nvidia's Kepler GPUs do not fully support DirectX 11.1.
This does not come as a big surprise considering that Battlefield 4 has been already pinned as a part of the upcoming AMD Never Settle bundle deal and Frostbite 3 might be one of the first, if not the first engine, that will have anything to do with DirectX 11.1, at least in actual game.
Source:
Techpowerup.com.