The FAQ says
"Initially we will only be supporting x86 architectures. With the Fedora
Core releases, x86_64 and amd64 architectures will become supported as
well."
x86_64 *is* the amd64 architecture, but RH and the kernel calls it
x86_64. I would change the above sentence to read:
"Initially we will only be supporting x86 architectures. With the Fedora
Core releases, x86_64 (AMD64) architecture will also become supported,
as well as other archs if they become mainstream Fedora Core in the future."