The following link contains an example of the new capabilities Inventor 2008 provides with its new "Export Geometry" tool used in conjunction with the updated "Derived Component" command. These tools enable a Skeletal Modeling workflow in which a change to the Skeleton will only affect the components using a specific set of derived geometry or parameters from it.
You could hypothetically have a skeleton with hundreds of parameters in it, and have hundreds of parts linked to these parameters in an assembly. When the skeleton is changed, only a small number of parts would need to "Update" in Inventor. This allows the technique to be used with much larger assemblies, and makes them much easier to manage in Autodesk Vault. Check out the example in this link:
http://www.screencast.com/t/0epJ8y1CTl
Ben with the INCAT CAD Geeks
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