From Fedora Project Wiki
Warren is trying to do the foolish task of figuring out if Apple MAC address prefixes are unique between PPC and Intel Macs. Please e-mail wtogami at redhat dot com if you have anything new to add to the prefixes listed below. I especially want to know if you found a MAC address that upsets the trend.
INTEL MAC
{{{ 00:16:CB Intel Macbook Pro 00:17:F2 Intel Macbook }}}
PPC MAC
{{{ 00:14:51 G5 00:0D:93 G5, G4 Powerbook 00:03:93 G3 iBook, G4 tower 00:30:65 G3 iMac 400MHz }}}