3dsmax, by Autodesk, for architecture and engineering, used by: Blizzard, Blur
Maya, also Autodesk, studios: Blizzard, Disney, Weta, Luna, Blur
Cinema4, for movies
Houdini, for movies, unique UI and workflow, used by: Blur, BlueSky
Zbrush, used by: Blizzard, Disney, Weta, Blur,
Lightwave
Arnold, used by Luna
XSI, used by Animal Logic
Marionette (Pixar proprietary)
Premo (DreamWorks proprietary)
Apollo (DreamWorks proprietary)
Blender, free open source, for gaming