How does the OpenACS aid those business styles? It provides a platform with CMS functionality, a concept of users, a system for users to contribute content via comments etc, a strong data model, some basic functionality on which to build services, and some site-wide services which allows your package to play nice with software yet to be developed. Out of the box it meets most of the needs of the first 2, many of the needs of type 3, and the basic needs of type 4.