Booted my machine today and it failed to find my LVM filesystems. Took a while to track down the issue. I didn't have lvm2 in my HOOKS array.
Pacman's logs show that the lvm2 hook was not processed when I upgraded to kernel26 (126.96.36.199-1) on 2010-02-25, however it was when kernel26 (188.8.131.52-1) was installed on the 2010-02-13.
I'm not sure what happened in between. I may have deleted the wrong file when cleaning up pacnew files perhaps.