How might ARM and x86 divide up the computing universe?

In a recent podcast I was a guest on over at The Digital Lifestyle, I got into a discussion with another guest, Jason Coombes, that was obliquely about the future of ARM, and the future of x86. I’ve been thinking about this conversation since.

As we know, post-PC devices sell rather well. These devices are typically run on ARM processors — these being “lightweight” processors that draw little power. (These devices also typically run on Unix — iOS being BSD-based, and Android being Linux-based....