When remotely updating a machine I had a problem where downloaded rpms in /var/spool/up2date were deleted but not closed when running "up2date -u" from an ssh session. "lsof | grep /var/spool/up2date" showed the files listed as "(deleted)" but open by an ssh process. Disk space was not freed. "df" output and "du -sk /var" output differed by the size of the deleted files. Logging out and back in via ssh did not close the files. Attempted to kill all sshd, which did not work either. Rebooting fixed the problem (obviously.)
fixed in forthcoming errata release.