I think the big thing that 3D visualization is really all about is collaboration. Great that you can create and show models with eDrawings or Doument3D or in a PDF. But the real value is in the ability to collaborate by sending around an interactive 3D model, rather than a bunch of 2D screen shots, or still renderings, and having the ability for people to comment, annotate, review, etc. 3D visualization is really about effective communication. Now one way is to just send around the 3D model and then have everyone email notes back and forth. That is certainly better than sending around notes about 2D screen shots. But it is better is if you can particpate directly on the document. This is where Adobe got it right. The Adobe reader allows virtually everyone to participate in the design review process and it’s free and available on Win, Mac and Linux. So anyone can create 3D collaborative documents using the Acrobat 3D Toolkit, and then save them so any one can use the free Reader and comment/collaborate. (any one from your manufacturing partners to upper management who may or may not be clued in to engineering email discussions, but can view model annotations)
So whatever distribution format eventually becomes the defacto standard - it has to facilitate communication. And it should do it in a way that does not separate the 3D model from the communication, and that makes it possible for anyone at any level in a company, to be involved.
A total aside, but I've got to also say that to me the smartest thing Adobe did beside the collaboration part, is the Acrobat Capture software. This breaks out of the lock of proprietary file formats and always needing to have the latest importers/exporters.