Phoronix published a review on the The New Features Of Linux 4.15: AMDGPU DC, RISC-V, EPYC Benefits, VR Improvements A quote from the article:

The merge window is effectively over for Linux 4.15 with it being the 14th day of the process, although 4.15-rc1 might not end up coming out today due to Linus Torvalds' traveling around the US Thanksgiving holiday. But with Torvalds tending to not approve major last minute additions to new kernels, we don't anticipate any last minute surprises and therefore here is our feature overview of the changes and new features of Linux 4.15. This is arguably the most exciting and feature-packed kernel update ever.

 The New Features Of Linux 4.15: AMDGPU DC, RISC-V, EPYC Benefits, VR Improvements @ Phoronix