That's essentially what gMax does. You draw a plan and elevations, then gmax shows the 3D Model. I realise that you already know that, so I'm wondering how the program you mention does it differently?
Where did you hear about it because I'm very interested in this subject.
I know of a program called Wings, that acts like a blob of clay. You pull or push the sides to create your final shape, but it's pure 3d. The only thing that comes near what you're suggesting is plug-ins for Autocad and Turbocad. There's also another less well known program which I can't recall the name of. These programs all allow you to draw in 2d, then the plug-in combines the elements to create a 3d model