Yeah that picture expalins a lot... FYI Open Season was done in Polys and converted to Sub-D/NURBS

NURBS stands for Non-Uniformed Rational B-Splines

NURBS is a geometry used by a lot of modellers to blockout there models prior to converting to polys then Sub-D. Some use NURBS as the only geometry to model from using the tools like attach/detach surface, Curves, Make/Fill Hole, the list is endless.

Look at your Maya Help Files (F1) and there are tutorials and information of NURBS and there uses, also there are loads of tutorials on NURBS Modelling online.

IMHO it gets great results, but it is very time consuming and not the fastest when it comes to tight deadlines. Use Polys and Sub-D's

Enjoy...