We are getting some pretty consistent feedback from our students that they are seeing some PMBOK Guide, 3rd Edition questions on the newly launched PMP Exam for the PMBOK Guide, 4th Edition. Needless to say, this can cause some anxiety in the exam prep process, especially for those folks that are studying only the 4th Edition.
In general, the questions seem to be around project selection methods and a few on Arrow Diagramming Method (ADM) / Activity-on-Arrow (AOA). As I've mentioned to the students, while this might cause some frustration to get these questions, given the relatively low number, it shouldn't cause you to fail the exam.
While I always coach to go for as many right answers as possible, the relative low occurrence of these questions would not necessitate additional study of the PMBOK 3rd Edition, in my opinion.