Cameron Scott of Timber Design in England has been using the 3D DWF for collaboration and loves it. Cameron does some really nice 3D work with timber framing and houses.
Check out Cameron's real world example 3D DWF
The 3D DWF is far more flexible than some of the other 3D document publishing options from CAD and contains much of the object data if you choose publish with it. It can also change the way the object is displayed such as hide, transparency, or isolate objects without having to re-publish the model separately with the different display types and other options. You can even choose to select the objects with the mouse by selecting them or by selecting them from the model tree "navigation" listing of objects each with their own object properties. The viewer is free and only a small 3MB download http://www.autodesk.com/dwf.
Most Autodesk products will produce the 3D DWF format very soon and currently you can produce 3D DWF from Autodesk Inventor 9 and Architectural Desktop 2005 with the 3D DWF Extension. 3ds max 7.5 is also going to have the 3D DWF as well, so imagine your 3D renderings now being small files with a free viewer in the 3D DWF with textures and the ability to navigate and selectively view specific areas or objects. Imagine what you could do with most all other Autodesk products outputting to the 3D DWF.
The 3D DWF is being used by many already in the design community to communicate in 3D without a large file or having to purchase anything to view them. Pretty cool and practical.
The 3D DWF is definitely not just a simple low resolution textured box lacking object data or display options like another recent 3D format in PDF version 7. Imagine you can either isolate a specific wall from a building model and get the properties of that specific wall in a 3D DWF, or you could simply have a 3D box with a texture where the building is essentially all one object with no intelligence.