6.0 and "options PREEMPTION"

Hello,

I'm confused about 6.0 and the kernel setting "options PREEMPTION".  I
was reading an article on OS News:

	http://www.osnews.com/story.php?news_id=10951

in which Robert Watson stated,

	One of the other nice benefits to the SMPVFS work is that
	with our fully preemptive 6.x kernel, not holding the Giant
	lock over the file system code lets the file system code not
	only preempt lower precedence kernel threads, such as
	background crypto operations or file system operations, but be
	preempted by more timing critical code, such as sound card
	interrupts, network I/O, and so on.

Does this mean that options PREEMPTION is assumed in 6.0?  If not, could
someone explain or point me to some docs that will help me understand.

-- 
Regards,
Doug