Well Nurbs and polys have been around since Jesus LOL but nurbs was more the organic method of modelling until Subdivision Surfaces became more popular in the industry because its basically derived from a polygon with a smoothing algorythm allowing for easier editing.

Nurbs have a bit of a texturing issue with stuff so with polys and subds you get the best of both worlds. It is dying out though some well known companies do like you to know them.

Yeah zbrush 3.5 is almost here, I'll be on the free upgrade list so Im especially stoked for it!!

Jay