This page is just getting off the ground. It will hold information about the Debian AMD64 porting project.
There are also helpful people on #debian-amd64 on irc.debian.org.
DebianAMD64Faq, possibly outdated.
Dual arch (AMD64 / IA-32) Installation, Documentation on how to make both archs work together and transparent to the users.
Dual arch (AMD64 / IA-32) Installation (Brazilian Portuguese), Translation of the above.
AMD64 port has finally become official. Here is what you need to do to your sources.list for the ?DebianAMD64MirrorMove (i.e. switching from an unofficial to an official mirror).
VerifyPAS, list of packages (erroneously?) tagged not suitable for different architectures in P-a-s. Your help is required!