Listed below are top-rated software names in each category. Note - there is a 'heavy bias' towards entertainment-oriented applications! The lists are indicative of where commercial CG is going..
If you get a job involving CG programming today, the programs mentioned below will figure in your life one way or another - you might work directly on the programs themselves (eg. at Pixar, Autodesk, etc.) or work at a movie/game studio where you'd write plugins/scripts to extend the programs' functionalities. That's the main point of the list below - these days, you hardly program CG from scratch!
Note - what's listed below are 'high end' programs meant for animation/vfx/commercials etc., not for developing games! In other words, game engines and middleware are not represented ("watch this space").
Note - RenderMan and Mental Ray are established high-end renderers with no compromise on image quality - that is why they are used to create CG to blend seamlessly with live-action imagery. They both implement global illumination, programmable shader capability, motion blur, depth-of-field etc, which collectively enable the synthesis of photoreal images.
More links [some overlap with above material]