Hi Johan,
in Photoscan this is not possible, and i doubt such a feature will be implemented in the future.
This is because a Quicktime VR is nothing more than an image sequence with a camera rotating around the center point of an object.
Some 3d rendering applications support rendering into Object VR though:
For example, you could export from photoscan into a 3d format (VRML in this case) and bring it into Cinema 4D and render from there a Quicktime Object VR out.
Best regards
Jan