I think it depends on how you are going to create and deploy your multi-domain "site". Django has a site structure: http://docs.djangoproject.com/en/dev/ref/contrib/sites/
which can allow you to implement the "news exchange" that you talked about.
django , , ( mod_wsgi , , virtualhost ), , /.
django django (1 ) virtualenv ( , ), python virtualenv.
, , :
project1
- coreapps/projectspecificapps...
- /
- /
- settings.py
- urls.py
- manage.py
project2
- coreapps/projectspecificapps..
- /
- /
- settings.py
- urls.py
- manage.py
, , APP python (, virtualenv).
/... . django django (, , wsgi?), , wsgi), , ..... "-, - .
http://www.b-list.org/weblog/2006/sep/10/django-tips-laying-out-application/
Django /
, , :
http://djangopackages.com/