X.org reference

[Puna Tannehill]

I know this question has been asked (and answered) before, but I'm 
unable to find it in the archives.  Is there a reference to the subtle 
differences between XFree86 and Xorg?  I was unable to find any 
documentation on X.org on installation and customization to use as a 
reference.

For example, I like to run 'XFree86 -configure' to do an initial probe 
and then customize the XF86Config it creates.  Things like that.

Or are keys held my our friend 'man' as usual and i should just wait 
for the port to complete?

Puna