> The first thing I think is "Why FreeBSD and not Linux?"

Because the GPL requires apple to release all of it's source code for any
changes it makes in the kernel.

> Regardless, the idea of a UNIX underbelly with a slick Mac 
> GUI system is like a dream come true.  The question is, can I 
> still get down and dirty into the UNIX side, does it still 
> feel like UNIX under the hood?
> 
> Anyone here tried out OS X yet?

You need to take a trip to the apple store at the mall of america.  OSX is
nice.  I really really want a G4 box so I can run it, but alas, I have other
things to spend my money on right now.  You can open a shell (tcsh I think)
and play around.  It's under the Utilities folder I think.  

Jay