heads up: new rawhide kernel doesn't boot for me

[Jim Meyering]

I updated my rawhide VM today (on F15 host), but it failed to reboot
using the new kernel, vmlinuz-2.6.39-0.rc1.git5.0.fc16.x86_64
I got a failure (VFS diagnostic complaining that the UUID-specified
root partition was not available), then panic.

Two subsequent attempts to reboot failed because even though I got
to the grub kernel-selection menu, I was unable to get a response
out of the interface, so couldn't select any other kernel or even
edit a grub stanza.  Luckily for me, on the third attempt, grub's
UI did respond to down-arrow and "ENTER", so I could select
the preceding kernel, and that one did manage to boot.

If necessary (i.e., if it's not already fixed), I'll file a BZ.