There's an extensive discussion at the moment on the python-dev list about how python modules and applications should be packaged up in future. This all relates to the distutils and setuptools features, which are great when they work and horrible when they don't. There seems to be general agreement that an uninstall feature would be useful.
My own point of view is that there are different requirements for installing applications for end users and modules for developers. In the former case I believe it would nowadays be easiest and least error-prone if each (Python) application were installed with its own interpreter and all dependencies. While this seems horribly wasteful, it neatly avoids any kind of version lock-in and allows application upgrades. In the latter case then something more like the traditional setup.py install is more appropriate, and the installation probably doesn't need to be recorded in whatever mechanism the system uses to record installed applications (e.g. Add/Remove Programs under Windows).
Whatever the result, it does appear that 2.6 could get us closer to a universal solution to installation problems.