To sum up what have happened so far;
1. I mistakenly moved the entire /usr dir to /export/usr
2. /usr was replaced with a link (usr -> /export/usr)
3. Problems become obvious after reboot
4. Restore
4.1. Mount root: /etc/mount -o remount,rw /
4.2. Delete usr link: rm usr
4.3. Re-create /usr: mkdir /usr
4.4. Restore files: mv /export/usr/* /usr
5. Reboot reveals that not all data made it to /usr as Scott finds several differences in the data I provide as we go along.
Newest things have been to manually create a /usr/sbin directory and copy all files from /sbin to it to fix a startup error (startup was looking for /usr/sbin/fsck).
As it stands, it cannot mount /dev/fd, and Scott have been puzzling a bit with where the data could've gone