Description of problem / Steps to Reproduce:
This morning, I did a "poweroff" as root at a console, but it didn't 
turn off my computer (only a black screen instead the turnoff), so I 
turned it off manually with the power button. This afternoon, I 
wanted to start FC2 again, but RHGB didn't start and the X server 
tries to startup, but crashs, tries to startup again, crashs again 
and so on.

The boot parameter contains "rhgb" and rhgb as well as the X server
worked with 2.6.5-1.358 and 2.6.6-1.427 before that shutdown using 
"poweroff". Notice, that it was the first shutdown with 2.6.6-1.427, 
I only did reboots with 2.6.6-1.427 before! Neither the old nor the 
new kernel changes anything, currently.

Version-Release number of selected component (if applicable):
kernel-2.6.5-1.358
kernel-2.6.6-1.427
rhgb-0.11.2-6
xorg-x11-6.7.0-2

Actual results:
Well, my X server simply doesn't startup, it tries to start, breaks
down, tries to start and so on... :-(

Expected results:
Working X server ;-)

Additional info:
Maybe you can find the problem out of my syslog file?

Hmm...I remember, that I reproduced the same or something similar 
with the same behavior (some time ago): I turned of my computer (not 
at a HP notebook) as it was running the X server. After turning on, 
the X server had this startup-crash cycle, too. Maybe that helps you?