I just took a look at what it does, still a bit confused to what it's supposed to do!
I do CAD professionally, and we use softwares like Rhino3d, Alias, Pro-E, Solid works etc. The important question that drives the types of software we use is, what is the out come for?
If I am a designer, still in the design exploration stage, I will use softwares like Rhino and Alias because they allow me more flexible tools for 3D modeling. If I am trying to create a more complicated form, such as cars, Rhino and Alias are also the right tools. However, for most production driven work, I will prefer Pro-E or Solidworks because it's more convenient to transfer the data to engineers.
So I was asking the same question when I am trying to find out what Adobe 3D is, and honestly, I didn't find a clear answer. It can generate 3D data, but only with very simple and limiting tools. So really, it's not ideal for any sort of 3D modeling. It seems to be good for generating textures for existing 3D models, particularly for 3D studio max models, but what for? Gaming? Animation? I don't think it's good enough for either use. For product design needs, there are already great and intuitive rendering softwares to do the job. Of course, photoshop is always needed for graphic needs, but never the 3D aspect of the software.
I hope Adobe has some real goal for this 3D department of the software and its future development, otherwise it looks quite half-assed to me now.