Install some dependencies: The use of apt-get here is wonderful because I didn't even have apache2 installed yet.

jd@hardy:~$ sudo apt-get install python-dev python-setuptools \
python-psycopg2 libapache2-mod-wsgi
jd@hardy:~$ sudo easy_install pylons 
jd@hardy:~$ sudo easy_install genshi

Set up a generic location for python egg cache:

jd@hardy:~$ sudo mkdir /home/pylons
jd@hardy:~$ sudo chgrp www-data /home/pylons
jd@hardy:~$ sudo chmod 770 /home/pylons

Enable mod-wsgi

jd@hardy:~$ cd /etc/apache2/mods-enabled
jd@hardy:/etc/apache2/mods-enabled$ sudo ln -sf ../mods-available/mod-wsgi.* .

Initialize your HelloWorld app

jd@hardy:~$ mkdir www
jd@hardy:~$ cd /var/www; ln -sf /home/jd/www jd
jd@hardy:~$ cd jd
jd@hardy:~$ paster create -t pylons helloworld
Selected and implied templates:
  Pylons#pylons  Pylons application template

Variables:
  egg:      helloworld
  package:  helloworld
  project:  helloworld
Enter template_engine (mako/genshi/jinja/etc: Template language) ['mako']: genshi
Enter sqlalchemy (True/False: Include SQLAlchemy 0.4 configuration) [False]: 
Enter google_app_engine (True/False: Setup default appropriate for Google App Engine) [False]: 
Creating template pylons
Creating directory ./helloworld
  Recursing into +package+
[...]

Notice the choice of genshi as the template language.

Configure your wsgi handler

jd@hardy:~$ mkdir ~/etc
jd@hardy:~$ cd etc; joe helloworld.wsgi

The helloworld.wsgi looks like this

import os, sys
sys.path.append('/home/jd/www/helloworld')
os.environ['PYTHON_EGG_CACHE'] = '/home/pylons'

from paste.deploy import loadapp

application = loadapp('config:/home/jd/www/helloworld/development.ini')

Edit your 000-default file

jd@hardy:~$ sudo joe /etc/apache2/sites-enabled/000-default

Add your WSGIScriptAlias

WSGIScriptAlias /jd/helloworld /home/jd/etc/helloworld.wsgi

Restart Apache

jd@hardy:~$ sudo /etc/init.d/apache2 restart

You should be good to go!