My swap partition is described as LABEL=swap in /etc/fstab, and is a real partition on the disk (/dev/sda6), not a volume handled by lvm. Previously in Fedora 8, the initrd worked by using "resume LABEL=swap". In recent initrd, the swap partition is described as /sys/block/sda//sda6, which is not the block device the system is expected to resume from. The result is that "resume /sys/block/sda//sda6" silently fails, and the regular boot continues. This problem seems introduced by the line suspdev=$(findblockdevinsys "$swsuspdev") in mkinitrd.
Changing version to '9' as part of upcoming Fedora 9 GA. More information and reason for this action is here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping
resolved in current rawhide