Sorry for being so late, I didn't get it finished until now (it took me ages to get the packages from ftp.archlinux.org).
I'm currently uploading "archlinux-2009.01-beta4-ftp-x86_64.iso" (the
new one, with grub-gfx revision 11) and all of the other images are
already queued for upload, though it'll take some hours until they are
uploaded. I'll upload a file ("Checksums") containing all of the
checksums of the files uploaded (and still to upload).
With these images it should be possible to perform an x86_64 installation without problems.
P.S.: In about half an hour the current upload should be finished.