I've been playing around with it on M1 Max since the Alpha build with great results.

Here's some numbers from my latest benchmark run:

    "Junk Shop" demo using Cycles
    M1 Max (10 cores CPU / 32 cores GPU)

    Blender 3.0 (CPU) / 1:14.64 minutes
    Blender 3.1 (CPU) / 1:10.86 minutes (1.05x)
    Blender 3.1 (Metal GPU) / 0:44.16 minutes (1.68x)
    Blender 3.1 (Metal GPU+CPU) / 0:27.90 minutes (2.67x)

For a reference, RTX 3090 (OptiX) was 0:18.22

Make sure you have macOS Monterrey 12.3 beta (the Metal backend requires 12.3 or above).

Let us know how that goes! I'm getting an M1 Max MBP sometime in the next two weeks and already know the very first thing I install on it after booting is gonna be Blender. It's a rite of passage for any new computer I acquire!

Update:

Initial testing on one of my low poly scenes:

v3.1 cycles GPU — 35.5 seconds.

v3.0 cycles CPU — 90 seconds.

3.1 with support for Metal and GPU rendering boosted speed by about ~ 3x

One of the most marvelous hobbies.