One final requirement that our end users had was that there should be a vertical menu system that would hide previously selected items and expend the current selection. The OOTB ASP.Net menu system did some of this but when displaying a deep hierarchy it didn't quite do what we wanted it to do. Dipping back into an OOTB publishing site and creating the predicted hierarchy to see how MOSS dealt with showed that after 3 levels the vertical menu gets truncated and a horizontal breadcrumb is created. The breadcrumb was the problem as none of our templates had a breadcrumb in. To resolve the issue we ended up buying the Telerik RAD Controls suite and using the Treeview for the navigation. The styling of the Treeview was done by adding the relevant CSS information into our site CSS.
With the deployment to our production environment, which so far has gone well, focus has moved to Phase 2. In the first part of this phase all the building blocks have been, or will be created, which include all the lists that will be used within the site.
Part of this phase will be using filtered lists - which seem like fun - where the user will select a value in one list and this will be used to populate another.