The unified view looks a lot like the the Stacked Layers view in earlier versions of Vectorworks. After all, it has the same icon. Do not be fooled, this is a big improvement in dealing with your building.
MacNN (http://www.macnn.com/articles/09/09/11/due.within.weeks/) tells it like this: A primary addition is the Unified View, which lets users work in 3D while retaining normal class and layer structure setups. The view also introduces VW09’s snapping technology into the 3D realm, including cursor queues and automatic guide and extension lines.
In practice, I reckon we will see people getting rid of the old layers we used to use to create a 3D model for viewing and creating elevations.