Mike, i think the BIM definition is different for each person. For example some people think of the BIM as containing everything, including all the details in a 3D model.
I think of the BIM as having choices, for example, i see the use of windoor as a kind of BIM. It appears in 2D/3D and has size and if i change it in the floor plan it changes in the window schedule. Roof, walls, joists are similar. We can asssign a database to doors, windows, beams, etc and report this information. This is under the definition of a BIM. I think we get a choice of how far we want to take it....