Blender 3.0 Will Have AMD HIP-Based GPU Acceleration
AMD has been working with Blender developers to improve GPU rendering by supporting AMD's HIP API in place of the removed OpenCL support. The HIP C++ Runtime API should offer better AMD GPU support than the poor OpenCL back-end of the past. This does require users though to be on the latest AMD Radeon Software Windows driver or on Linux with the Radeon ROCm driver stack in place and working or their Radeon Software for Linux packaged driver stack.
AMD currently has validated the Radeon PRO W6800 and Radeon RX 6000 series for use with Blender 3.0's Cycles X HIP support. Other HIP-supported AMD GPUs may also work but for now AMD is just validating their RDNA-based hardware. Those wanting to try out this AMD HIP support can use the latest Blender 3.0 daily builds.
More details on the now-ready AMD HIP support for Blender 3.0 via code.blender.org.
Blender 3.0 should be released in December. I'll have up plenty of Blender 3.0 NVIDIA GeForce vs. AMD Radeon benchmarks in due course.
Update: While it looked like they would have AMD HIP support in the Blender 3.0 Linux build, it's looking like that support won't be enabled until Blender 3.1, so for now will be just Windows-only.