The INS wants you score 80% or better on an oral version of this test.
I scored 90% and will make the usual disclaimer that at least one of the questions I got wrong was not particularly germane to being a good citizen. It was something that most folks would look up rather than remember.
How well did you do?
Here is the current list of possible questions (PDF) with answers.
In the new pilot exam (PDF) applicants are required to anwer only 6 out of 10 questions during the pilot period.