Have a look at this SO question. It explains all the packaging methods very well, and might help answer your question to some extent: Differences between distribute, distutils, setuptools and distutils2?
Distutils is still the standard tool for packaging in Python. It is included in the standard library (Python 2 and Python 3.0 to 3.3). It is useful for simple Python distributions, but lacks features. It introduces the distutils Python package that can be imported in your setup.py script.
Setuptools was developed to overcome Distutils’ limitations, and is not included in the standard library. It introduced a command-line utility called easy_install. It also introduced the setuptools Python package that can be imported in your setup.py script, and the pkg_resources Python package that can be imported in your code to locate data files installed with a distribution. One of its gotchas is that it monkey-patches the distutils Python package. It should work well with pip. The latest version was released in July 2013.
So, as you can see setuptools should be preferred to distutils, and I see where your question comes from, however I don’t see distutils losing support anytime soon, as, simply put, it is used in many cases with some popular legacy programs. And as you probably know changing these sorts of things in legacy programs can be quite a pain and come with quite a few problems, for example incompatibilities, which would then lead to the developer having to rewrite the source code. So there is that, and also the fact that distutils is a part of the standard python library whereas setuptools is not. So, if you are creating a python program, in this day and age, use setuptools, however keep in mind that without distutils, setuptools would have never existed.