Board identification effort

Good day.

I've read this thread on how to correlate a unique ID-like quantity
printed on the BeagleBoard xM board and a corresponding quantity that
can be read programmatically from the kernel.

My interest is the same as the original poster's, that being an aid to
auto-provisioning. The thread ends with the conclusion that this is

a) I wanted to check back to make sure the answer is still

b) where in the Angstrom build is the USB/Ethernet MAC address
determined? I notice this quantity varies from boot to boot.