This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
In the exam, if there is a question which asks if GET is idempotent (without code or without any effect in the code), the answer will be true.
But if there is a question with a GET method that is not idempotent (which updates the database by example), the answer will be false except if we see "according to the HTTP spec", the answer will be true.