When using kdm and choosing reboot, the system often changes to the
console for 1 second and then tries to restart X. Therefore you
do not see any console messages. X is stopped right when the
md messages ("recovery thread got woken up" etc.) are displayed.
I did already see this in 7.0 (with KDE 2.0.1 installed) but thought it was
because of my, well, "unusual" installation.
I can't really reproduce when this happens, but switching between X and
the console and doing some telinit 3 and telinit 5 definitely helps ...
(This was with both XF3 and XF4 using different computers with
different hardware components.)
When using gdm instead I do not experience any such problems.