You let the package manager manage whatever you are not very interested in (something you don't care with recent version you are running). I'd never let it manage something I can manage better.
http://guide.python-distribute.org/introduction.html#current...
http://tarekziade.wordpress.com/2010/02/10/pep-345-and-386-a...
It's confusing but improving quickly. I know it took me quite a while to figure out what the right way to do things in python was.
This is also where rails' conventions help. As good as people say the documentation for Django is, many searches pull up blog posts from 2006 which were right for their time but now are simply outdated. That being said, I think there has been a tremendous boost in Django activity in the past year or so. I feel like they are getting in front of the curve again.
I recently started getting hot and heavy with Linux after moving my stuff to EC2. I thought package managers were the bee's knees until I realised that my production server and my development box (at home) we're running drastically different versions of the same program/library. This of course caused a whole bunch of incompatibility problems and headaches when it came to building other stuff.
If you care about versions and stability, it's just safer and more reliable to compile from source that you know that works. Package managers can sometimes be a crap shoot.
Installing from tar.gz isn't at all complex or difficult, either. The article would have been much more helpful if the author knew more about Python and Django.
Source: http://packages.ubuntu.com/search?keywords=python-django