Initial support for OSL has been added to the GPU renderer. As in the CPU renderer, you can mix and match OSL and Arnold shaders in the same shading network. Note that this initial support is still not complete and currently has a number of limitations as listed below.
Currently, there is limited support for specific shading operations, as follows:
The GPU renderer supports OpenVDB and matches the CPU renderer visually quite well and is feature-complete. The match with CPU will become increasingly good as the step-size parameter is reduced.
Initial support for volume displacement has been added to the GPU renderer. The rendering speed may be slower than CPU in cases with high opacity volumes, as the GPU implementation does not skip empty space as efficiently as the CPU version. The match with CPU will become increasingly good as the step-size parameter is reduced.