ANCC: a lot of nonclinical based questions (including in the management questions). if you are strong in guessing correct answers nor strong common senses, just like me, don't take it. (I failed in this test in August). However, questions are very short and not too much senario type questions. It is different from what I did from most of the review questions books.
AANP: a lot of clinical based questions(the more knowledage you have from your review and practice questions, the more chance you can pass it). The questions types look so alike from the review questions book writien by Margrant Fitzerglad (sorry if i spelled it wrong). Try to remember and understand the rationales of every single answer from each questions. If you do it, I am sure u can pass the test. (I passed the test for ANP in September 17, 2012). Hope this sharing help you those are preparing for the exam. Good luck! and God Blesses you all as always!