[ros-users] Improving Stack Installation

So I was reading the documentation one day and I saw this.
http://www.ros.org/wiki/ROS/Installation/Ubuntu/Deb
sudo apt-get install ros-boxturtle-slam-gmapping

This appears to install the slam-gmapping stack in a debian compatible
form that is very appealing for some of our work. Unfortunately, it does
not currently work with our stacks. Will/Could non Willow Garage stacks
be added in the future or should we look at rolling our own system?

Is there anything that is special about the process of building .deb
files that could be documented or it is just using standard debian
package management tools?

This brings to mind another stack question, right now it appears that
there is no way to easily determine what is the installation directory
for a stack. The documentation for our stacks assume that you installed
ROS from svn, compiled and you want to compile the stack from source.

{{{#!shell
cd ~/ros/stacks
git clone http://robotics.ccny.cuny.edu/git/ccny-ros-pkg.git
}}}

This is probably confusing for people who did not build from SVN since
things can be installed using apt-get. How can this be improved?

Is there a way to determine the full path of the primary stack directory?
$ROS_PACKAGE_PATH returns a list that usually has one item.

If there is more than one item which is most likely the primary path
where new stacks should be installed?
The first or the last element in $ROS_PACKAGE_PATH?

Perhaps something like this could work.
{{{#!shell
cd `rospack stack-install-dir`
git clone http://robotics.ccny.cuny.edu/git/ccny-ros-pkg.git
}}}
where `rospack stack-install-dir` prints out the (first/last) value of $ROS_PACKAGE_PATH
or the value of $ROS_STACK_INSTALL if set.

Is there already another way of doing this?