What are the responsibilities of key staff members in an anime production? With any given series, there's a lot of names and titles being thrown around in the opening and closing credits.

What are the typical key roles (E.g., art director, color-setters (iro shitei), producer, director, series coordinator) and their primary responsibilities? Are there also any roles or departments exclusive or work differently in anime production than in traditional or western animation?
There's a pretty good summary of a lot of the positions here.  


Original Creator
Director
Enshutsu (Animation Technical Director)
Character Designer
Animation Supervisor
Key Animators
Inbetweeners 
Producer
Art Director (Art Model and Background)
Color Coordinator
Finisher
Special Effect / CG Artist


These are just a few highlights:


  Original Creator (gensaku)
  The original creator is the person who came up with the concept for
  the story originally. This may be the original manga creator, a
  novelist, game developer, playwright, author, oracle, prophet, or
  whoever can come up with an original idea.
  
  Enshutsu
  Often translated as animation director or technical director. Enshutsu
  is one of the most difficult and most important jobs in the Japanese
  animation industry. The enshutsu is between the director (kantoku) and
  the production staff. He is responsible for checking and supervising
  the show through the production, from initial story to the final
  released product, and in many cases, has almost total control over it.
  He checks the animation drawings as they are being done, sets up the
  scenes before they go to camera and supervises the sound and voice
  recordings and all the editing amongst many other jobs. The exact job
  and responsibilities vary from company to company, and from show to
  show as well. Sometimes the enshutsu ends up as the whipping boy for
  the director; sometimes he or she carries the show and the director
  sits back and watches. On larger productions there is sometimes more
  than one enshutsu and usually quite a few assistants. It is important
  to have a good knowledge of animation production as well as artistic
  talent to do the job and it usually takes four or more years in the
  industry before someone can do the job right.
  
  Inbetweening (douga) The inbetweeners use the key drawings as reference points and produce drawings that fit between the
  positions on the keys. This smoothes out the movement and makes the
  animation look better. (The more inbetweens there are, the more fluid
  the movement becomes and the more expensive the animation becomes.)
  Inbetweening is a relatively non-creative job. It is more tracing than
  anything else. The hours are long and the key animators are sometimes
  very hard to work with. The cruelest part of being an inbetweener is
  that they rarely get to work on anything they are fans of and what
  they do get to work on they burn out on quickly. (I know some
  animators and an enshutsu that you can send into convulsions by
  whispering "Ranma" in their ears.) After 2 or 3 years of grueling
  inbetweening, animators who can handle it are usually promoted to
  keys.


As for a position that is present in anime production but not as common in western or traditional animation, I could could only find one position that might fit the bill.


  Color Coordination (Iroshitei)
  The Color Coordinator decides all the colors for everything that will
  be painted/colored by the shiage department in the show and creates an
  iroshitei hyou (color model pack) that the staff can refer to when
  painting. This job requires not only good color sense but a good
  memory, as the CC should be able to keep an idea of what the colors
  for the whole show look like in her head so that when questions come
  up about small details and things not in the iroshitei hyou she
  doesn't need to pull all the models and think about it.
  The CC makes
  color models of each of the characters and the props, mecha etc. in
  the computer paint system. The painters use these models when coloring
  the various scenes.
  In the old days of liquid paint, there were 327
  commonly used Taiyou Shikisai (Taiyo Paint Company) cel paints but
  they had over 1,000 in their catalog. Each color had a code number
  which originally was its equivalent to the DIC (Dai Nippon Ink
  Company) code. Color code numbers were usually a letter followed by
  numbers like GY-40 and RP-99. (Some companies used another paint
  company - Stack - but their paint was more expensive (and higher
  quality) and the paint codes were different.)
  A good way of telling
  that you had done this job too long is when you lookout a train window
  at a sunset or forest and find yourself determining what paint colors
  they it is composed of. Computers have made life a lot easier with
  16.7 million colors ending the need for weird paint codes but now you look at that sunset and wonder what dpi you would have to scan it in
  to get good output quality.


I'm sure other types of animations have color coordinators but this one is somewhat specific to anime since it deals with a specific Asian company and their limited paint color selection.

The full page is worth a read as it has a lot of the Japanese names of positions in addition to their translated names.