The most important parts of this video and worth noting are the following points.
The new HD engine will switch all player model rendering to the GPU - I'm not sure whether this also applies to bullet mark decals and brass.
The new bottleneck, the real killer of HD maps will be complex, multi stage shaders, where possible mappers should switch from using shaders to only images which have bump and normal maps. Obviously, for special textures like glass or water, a shader is unavoidable.
It may now be possible to construct larger, more open maps. The efficiencies in the new HD engine and the switching of player model rendering to the GPU frees up a lot of processor time.
Use light entities in map, many and of low intensity to give more realistic lighting. Light entities create light and shadow maps at the compile stage and are not processed at run time