Michael Girouard has posted his
10,00 foot view of the typical structure of an Model/View/Controller application (and framework) and how a page request is handled:
In my previous article, I announced that I would be documenting the process of developing a simple MVC framework. In this post I will go into a little more detail about each of the specific components of our MVC and will discuss the series of events which occur each time a page loads, otherwise known as the page load scenario.
He talks about how URIs work, the role of mod_rewrite, several of the objects involved (like the Front Controller, Request, Route and View) and how they all fit in with the custom Models, Views and Controllers the user could define.
Michael Girouard's Blog: Rolling Your Own MVC: The Page Load Scenario - Read More... 
