The keynote showed them running Linux under Parallels, although that was a version of Linux compiled natively for ARM (which would seem to be preferable to runn

The keynote showed them running Linux under Parallels, although that was a version of Linux compiled natively for ARM (which would seem to be preferable to running it with Intel emulation, speedwise). VMWare has also strongly hinted that their stuff will work on ARM-based Macs. "Not supported by Apple" doesn't necessarily mean "can't be done".