I have been asked some questions off-list which might be generally useful, so 
I have paraphrased the questions and replies here;

Where are the ebuild equivalents?
How do I create a distro?
How does package management work?
Can I create binary packages?

The rubyx script does everything. The ebuild equivalents are included in the 
script; search for Pkg_ and have a look for yourself

You can create a distro with something like

rubyx --root my/distro/root --cpu pentium4 -cflags -O2 --distro kde xemacs 
apache

Once you've got it installed and booted, you can install/uninstall extra 
packages like this

rubyx --install samba
rubyx --uninstall apache

And when a you get a new version of rubyx, you can upgrade your packages like 
this

rubyx --upgrade all --keep

Rubyx doesn't have any binary package support built in as it builds everything 
from source, but you can create a binary package easily like this

tar -cjf samba.tar.bz2 /pkg/samba

and install it on another machine like this

cd /pkg
tar -xjf samba.tar.bz2 /pkg/
rubyx --relink

Hope that clarifies things abit.

Andrew