I installed mod_wsgi and really like it a lot. Its a lot like mod_fcgid in some ways, and is really helping me experiment with serving python-powered content. Cool!
When working on Nexista, I started to architect applications like PBooks so that each main part would have a separate entry point. For example, to login, you would access the auth.php script, and the various functions and resources could be accessed with keys, like auth.php?nid=login. Once you logged in to the application, you would interface with the pbooks.php entry gateway, and access its functions and resources in the same manner.
This jives very well with mod_wsgi and the plans I have for Schematronic. I'm still on the fence about how much I want Schematronic to be like Nexista or Cocoon / Pycoon, as I'm more familiar with Nexista, but Cocoon is bigger and has more support.