I guess, it's easy for me to imagine a shape - i can draw that shape on a piece of paper, but i find it hard to express that same shape using modeling software.

Say, wrap some text around the surface of a sphere. I'm pretty sure i could, letter by letter, orient and kern text in OpenSCAD but it would take me a long time to do.

i imagine in the not to distant future there will be a motion tracker or kinect app to allow shaping stuff like clay - or maybe just use clay and scan it in.

In any case, all the software i've used feels clunky. iMovie for modeling will be a big deal.