I do wonder if some of the users Paul heard from confused the 7 and 8 exams, or didn't remember the material accurately. After all, the test is hard and it's easy to be overwhelmed. It's highly unlikely when Oracle explicitly removes an objective from an exam, like the removal of the PreparedStatement from 7 to 8, for it to then appear on the exam. We certainly haven't heard any such feedback from any of our readers.
While the depth of an Oracle objective may be subjective, the existence of it is usually not. For example, if StringBuilder is in an objective, then you need to know about it, but which methods in particular requires an element of common sense. Sure, you can study every single method in the API, but given the broad scope of the OCP exam, that's bound to be exhausting. In our books, we focused on the most reasonable requirements, while also incorporating suggestions from our readers including our own experiences taking the exams.
Likewise, if Oracle drops Callable statements or ResultSetMetaData as objectives, then you can sleep well in knowing you don't have study for it. Not that these aren't important topics, but as I said, the scope is broad so you're better off focusing on what you know is on the exam.