I think most people here are not understanding the target audience for this tool (hint: it's not for your typical linux environment). It's not about package management or having a universal installer... it's about being able to run your application in a different environment where you don't have admin rights.
In a lot of university clusters or compute grids researchers have access to a large collection of compute nodes, but they usually don't have any rights to those machines. In fact, most of the time the programs are ran in a sandbox and have a restrictive environment. To run their codes reliably, researchers often have to perform some sort of static linking or package up all of the dependencies with the executable. apt-get or yum are not options in these environments... you may not even be able to ssh into them. Ideally, you could ask the system administrator that controls the cluster to install certain packages, but again, this is not always possible particularly if the researcher requires a niche package used in their domain.
Moreover, the cluster may be composed of heterogenous set of machines with different versions of Linux. Package management does not help you here. The only way to reliably execute your programs on such a heterogenous cluster is to statically link or include your dependencies. If you are wondering who would use such a maddening environment where you have no admin rights... google Condor, OpenScienceGrid and Globus. This is how a lot of research computation is done.
Of course, the hot new thing is virtual machines and clouds... but firing up a VM each time you want to run an application is very heavyweight... especially if your applications has a short run-time.
TL;DR: this isn't for your typical ubuntu or fedora install; it's for scientific research that is done on restrictive computing clusters and grids.
As a side note, I made and use a much cruder tool http://bitbucket.org/pbui/starch/ that packages everything up (executables, libraries, and data) in a self-extracting tarball which can be executed on remote hosts. It's not as slick as CDE, but it's been used with success by various research groups that I collaborate with.
Torque is cheap.