If you're an Inventor user, you will need to get hold of something called the Autodesk Inventor 11 DWF Extension in order to take advantage of all the cool new features such as round trip markup and publishing your Inventor parts list into DWF. You can get the Inventor 11 DWF Extension from here, but note that you will need to be on subscription to get the goodies.
And most importantly of all, if you're using Vault 5 or Productstream 5 you need the Hotfix: DWF Extension for Autodesk Design Review 2007 and DWF Viewer . This hotfix enables Vault 5 and Productstream 5 clients to view DWF files generated from Autodesk Design Reviewer 2007 within Vault Explorer or any of the Productstream clients. IMPORTANT to remember though, this hotfix does not include Design Reviewer 2007 - you will still need to contact your reseller or Autodesk sales representative to get it.