Well, let me see what I can clarify, even though I've not taken the non-Beta version (though I have done so with other exams that I have taken the beta for.)
The reason for the shorter time limit and fewer questions is that the Beta exam actually tests a broad selection of the question pool for the general-release exam. Whereas most of Sun's exams have 51 questions, the Beta usually has closer to 200, and appropriate time to allow the candidate to leave comments for those questions. (I tend to be verbose, and sometimes inane, with said comments.)
No question on any in-center Sun exam involves actually manually writing/compiling code. (Please don't give them ideas.) The only exam that actually involves writing real code that's going to be compiled is the
SCJD, which involves a practical, do-at-home section. The rest are a combination of multiple-choice, drag-and-drop and fill-in questions.
So, to answer the last question - they do not (generally) drop too many questions from the beta. From the questions used in that beta, there is a pool prepared from which the exam is drawn. The only ones who could answer as to whether questions were added/removed after that Beta would be the folks at Sun's training division.
Hope that helps.
