Ok, problem solved:
1) press 'a' at startup to edit kernel arguments.
2) append 'acpi=off' to the end of the line (after rghb quiet)
3) press enter and boot should succeed.
4) once you have logged in, open a terminal, and as root, type: 'yum update pcmciautils'
5) After this, reboot and it should all work fine.
Turns out the two error messages aren't really that critical. My real problem was at udev, which causes the kernel to hang. Caused by pcmcia.
bugzilla for this problem