Zope:
  http://cheeseshop.python.org/pypi/zope.testbrowser/3.4.2

  Browser-centric (vs. application-centric)
  Slightly verbose
  Works over HTTP (WSGI with wsgi_intercept)
  Has forms, etc (Mechanize)
  Next best (after WebTest)

Django: 
  http://www.djangoproject.com/documentation/testing/

  Reasonably system
  Slightly verbose
  Works over Django request system (not WSGI)
  Slightly leaky
  No forms

CherryPy/TurboGears 1:
  http://docs.turbogears.org/1.0/Testing#testing-your-view

  Very leaky!
  Tests happen via side effects
  Global objects everywhere
  Can call directly into controllers
  No forms

Rails:
  http://manuals.rubyonrails.com/read/chapter/28

  Call directly into controller
  Actually instantiate the controller in your tests
  The main functionality is in a TestCase subclass
  Has some XML/HTML inspection
  Vigorous debate on best practice:
    http://www.anarchogeek.com/articles/2007/9/16/rails-where-the-boundries-are-pushed
    This is not a good thing
    Mocks all over the place :(

----

Twill:
  http://twill.idyll.org/

  Works over HTTP (WSGI with wsgi_intercept)
  Lots of form support (Mechanize)
  Simple-looking tests
  Not a complete language

Selenium:
  http://www.openqa.org/selenium/

  Works in a browser
  Awkward language
  Recorders exist
  Satisfying to watch run

Windmill:
  http://windmill.osafoundation.org/

  Like a mix of Twill and Selenium?
  Uses a browser IDE like Selenium
    Fancy Javascript recorder?
  Experimental command-line
  Browser can report back to code, like the (confusing) "drive" mode
    in Selenium