> 1) Most (all?) free Unices use XFree86 by default; that includes Linux,
> FreeBSD, OpenBSD, NetBSD, etc.

Nope, not XFree - they run X11R6, R5, R4 and even R3. I just visited the X.Org 
FTP - X11R6.6 is there for download - since April 21 2001. They're slow as 
molass...

So yes, FreeBSD, NetBSD, OpenBSD and the free unices uses XFree86, but HP-UX, 
Solaris, SGI's Irix, and OSF/1 (Tru64) uses their own X server, not XFree86 
(I even got an email from Sun which doesn't recommend XFree back then when I 
had problems with an Ultra 60 machine)

> 2) XFree86 is pretty much the standard way of supporting the X11 protocol
> on non-Unix systems, such as MacOS X, OS/2 and Windows.

Excuse me? if you want X11 protocol support on WIndows you'll need either 
Interix, Cygwin, or a free X server. Interix does a very good job as it gives 
you an X windows which just looks like a standard Win32 windows.

> 3) Sun has expressed interest in supporting the RENDER extension in their X
> server. Solaris can also run XFree86.

Expressed - maybe. A friend of mine which tested Solaris 9 told me Render is 
not there (I didn't test it myself - correct me if I'm wrong).

Hetz