If I set the settings on one of my posts so that only a certain group of people can see it, can those people see the list of people who can see the post?
If you set the audience to one of the friend lists that you created, or to Close Friends or Acquaintances, the people on that list will be able to see the names of the people that can see the post (but not the name of the list). If you set the audience to one of the "smart lists" that Facebook creates automatically based on family/city/school/work, those people will be able to see the list name and not the individual names. Facebook does this to help people decide whether they want to like or comment on the post, since those same people will be able to see their like or comment.
Additional information can be found in this answer.